Senate Race Summary for Nov. 3:
Bad news for the Democrats: Tennessee has shifted to "lean" Republican. The latest survey from Rasmussen Reports shows Republican Bob Corker leading Democrat Harold Ford by eight points; other polls in the last week have shown Corker up by eight points (CNN/ORC) and 10 points (Reuters/Zogby). These increase Corker's lead on our last-five-poll average to 4.6 points (50.0 percent to 45.4 percent), just enough to move this state to "lean" Republican.

Arizona may be a ray of hope for Democrats. A new survey by the Arizona Daily Star shows Republican Sen. Jon Kyl leading by just five points (46 percent to 41 percent). While Democrat Jim Pedersen has been slowly gaining support, this new margin is closer than in other recent polls. Nonetheless, it still narrows our last-poll average just enough to shift Arizona from "strong" to "lean" Republican.

Senate Race Summary for Nov. 2:
Montana is now a tossup. That makes four. A new Reuters/Zogby poll showing Democrat Jon Tester leading by Republican Sen. Conrad Burns by just a single statistically insignificant percentage point (47 percent to 46 percent) confirms a Rasmussen Reports poll from last week showing the race closing. Two weeks ago, Tester ran seven points ahead of Burns on our last-five-poll average. Burns has since cut that advantage to just 3.2 percentage points (48.2 percent to 45.0 percent), just close enough to move Montana to tossup status.

So, the race for the Senate is all tied up, with 48 seats either held or at least leaning to each party. To gain control of the Senate, Democrats will need to win three of the four tossup states: Missouri, Tennessee, Virginia, and, now, Montana.

Senate Race Summary for Nov. 1:
Polls are starting to come in fast and furious now. Ten new polls since our last update leave the three remaining tossup states—Virginia, Missouri, and Tennessee—looking as close as ever. Looking at our last-five-poll averages, Missouri Democrat Claire McCaskill runs just four-tenths of a percent ahead of Republican Sen. Jim Talent (48.2 percent to 47.8 percent). In Tennessee, Democrat Harold Ford trails Republican Bob Corker by sixth-tenths of a percent (46.8 percent to 47.4 percent). And, finally, in Virginia, Democrat Jim Webb now runs a point and a half ahead of Republican Sen. George Allen (48.4 percent to 46.8 percent). None of these leads is statistically meaningful. All three races remain too close to call.

Senate Race Summary for Oct. 30:
New Jersey is back in the blue. Two new polls since our last update show Democrat Bob Menendez leading Republican challenger Thomas Kean Jr. by five (Rasmussen Reports) and six points (Research 2000). These collectively increase the average Menendez lead in our last five polls to 4.2 points (45.4 percent to 41.2 percent) and move New Jersey back from tossup to "lean"-Democrat status.

Thus, the Democrats now have a 49 to 48 seat advantage in the race for the Senate. They will need to win two of the three remaining tossup states—Missouri, Tennessee, and Virginia—to gain majority control.

Speaking of which, the release of two new internal polls from the Democrats leave the tossup status for Tennessee and Virginia unchanged. A poll for the Democratic Senatorial Campaign Committee shows Democrat Jim Webb leading Republican Sen. George Allen by four points, while a new internal poll for Democrat Harold Ford shows him leading by five points. The two new polls bring our last-five-poll averages to virtual ties. Allen leads by four-tenths of a percent in Virginia (46.6 percent to 46.2 percent), while Tennessee is a dead-heat tie (46.8 percent to 46.8 percent).

Senate Race Summary for Oct. 27:
A new Rhode Island College poll shows Democrat Sheldon Whitehouse leading Republican Sen. Lincoln Chafee by 10 points (43 percent to 33 percent). Since that margin is better than Whitehouse's six-point lead (45.8 percent to 39.8 percent) on our last-five-poll average, it moves the momentum meter in the Democrat's direction. For now, at least, Rhode Island remains in the "lean" Democrat column.

In Tennessee, two new polls since our last update move the momentum meter back to neutral. A new poll by Democratic pollsters Hamilton Beattie & Staff shows their client Harold Ford with a statistically insignificant two-point lead (47 percent to 45 percent) over Republican Bob Corker, while a new independent poll from SurveyUSA shows the race tied (48 percent each). With the addition of the new polls, our last-five-poll average shows Corker leading by the narrowest of margins (47.8 percent to 46.2 percent).

Senate Race Summary for Oct. 26:
With less than a week to go, the race for the Senate looks closer than ever. A new Rasmussen Reports poll in New Jersey shows a dead-even race between Democrat Bob Menendez and Republican Tom Kean Jr. The new result narrows Menendez's lead on our last-five-poll average to four points (45.4 percent to 41.4 percent), just enough to shift New Jersey from "lean" Democrat to tossup, at least for the moment. So, the overall scoreboard shows both parties with 48 seats they either currently hold or at least lean in their direction.**

Four states—New Jersey, Missouri, Tennessee, and Virginia—are now tossups.

Two new automated polls in Virginia confirm that the gap there is narrowing. SurveyUSA shows Republican Sen. George Allen leading Democrat Jim Webb by three points (49 percent to 46 percent). Rasmussen Reports shows Allen up by a single point (49 percent to 48 percent). The new last-five-poll average gives Allen a lead of less than two points (47.6 percent to 46.2 percent). Allen is narrowly ahead on four of the last five polls, but the nonsignificant margin leaves Virginia looking dead even.

**Note that our scorecard treats both Connecticut's Joe Lieberman and Vermont's Bernie Sanders as Democrats because both have pledged to caucus with the Democrats if elected. Of course, neither are Democratic Party nominees. Sanders is running as an independent and Lieberman as a member of the "Connecticut for Lieberman" Party.

Senate Race Summary for Oct. 25:
Virginia is a tossup, which means our scoreboard now shows the Democrats with a lead in the race to control the U.S. Senate. Forty-nine seats are currently either held by Democrats or lean that way, while 48 seats are held by or lean Republican. Democrats will need to win 51 seats to gain majority control (since Vice President Cheney will cast a tie-breaking vote for the Republicans). So, they will need to hold their current leads and take two of the three remaining tossup races: Tennessee, Missouri, and, as of today, Virginia.

In Virginia, a new poll from the Los Angeles Times and Bloomberg is the first random-sample survey to show Democrat Jim Webb leading Republican Sen. George Allen (albeit by a statistically insignificant 47-percent-to-44-percent margin). The new poll indicates new momentum for Webb, but, more importantly, narrows Allen's lead on our last-five-poll margin to less than four points (47.4 percent to 44.0 percent), just enough to move Virginia to the "tossup" column.

In Missouri, two new polls indicate new momentum for Republican Sen. Jim Talent. The polls from L.A. Times/Bloomberg and SurveyUSA both show Talent leading Democrat Claire McCaskill by the same statistically insignificant three-point margin (48 percent to 45 percent). Other recent polls, including the Mason-Dixon survey released just yesterday, showed McCaskill slightly ahead, so McCaskill holds on to a one-point lead (46.2 percent to 45.2 percent) on our last-five-poll average.

Senate Race Summary for Oct. 24:
In Tennessee, two polls out today show new momentum for Republican Bob Corker. The surveys, from Mason-Dixon and Rasmussen Reports, both show Corker running a statistically insignificant two points ahead of Democrat Harold Ford. Since previous polls had shown Ford up (on average) by a few percentage points, our momentum meter now points to Corker. However, our new last-five-poll average shows Ford at 47 percent and Corker at 46.4 percent, making Tennessee the mother of all tossups for 2006.

The Mason-Dixon organization also released polls today for another eight races on our Senate Scorecard. The other polls are generally consistent with our averages, although they show the Democratic candidates leading by slightly closer margins in New Jersey (+3) and Montana (+3) than on our averages of other recent polls. However, these new surveys indicate no new momentum for any candidates outside Tennessee.

Senate Race Summary for Oct. 19:
In Maryland, a new poll from SurveyUSA provides some good news for Republican Michael Steele. The latest survey shows him running dead even with Democrat Ben Cardin. Although Cardin continues to lead by more than seven points on our last-five-poll average (49 percent to 41.8 percent), the new survey points the momentum arrow in Steele's direction and lowers our assessment of Maryland from "strong" to "lean" Democrat.

Note, however, that unlike other pollsters, SurveyUSA also showed a very close race on its last Maryland poll in mid-September. It showed Steele running one point ahead of Cardin, while four other surveys conducted in September showed Cardin leading by margins ranging from 5 percentage points to 11 percentage points. Does this new poll indicate a trend or a "house effect" unique to SurveyUSA? We will need more polls to know for sure.

Senate Race Summary for Oct. 18:
The state of Ohio provides yet another reason why our big momentum arrow continues to point in the Democratic direction. New polls released over the last week show Democrat Sherrod Brown leading Republican Sen. Mike DeWine by margins of 14 points (SurveyUSA), six points (Rasmussen Reports), seven points (University of Cincinnati), 12 points (Quinnipiac University), and 13 points (CBS/New York Times). Brown's lead on our last-five-poll average more than doubled over the last week, from five points to 10.4 (51.6 percent to 41.2 percent). Ohio, considered a "tossup" race for much of the year, now moves on our scorecard from "lean Democrat" to "strong Democrat."

Senate Race Summary for Oct. 16:
The story for today is Jim Webb momentum in Virginia, as measured by two new polls with nearly identical results (Washington Post and Rasmussen), although it's not quite enough to change the "lean GOP" status. This strong showing may be the result of the Democratic Senatorial Campaign Committee coming to Webb's aid. Before, Republican Sen. George Allen owned the airwaves. Now, Webb is running ads attacking his opponent.

Senate Race Summary for Oct. 13:
In Missouri, three new polls show Democrat Claire McCaskill either leading Republican Sen. Jim Talent by nine points (SurveyUSA), leading by five (an internal Democratic Party poll), or trailing by one (Rasmussen Reports). We continue to classify Missouri as a tossup due to McCaskill's margin of only two points on our last-five-poll-average margin (45.8 percent to 43.8 percent), although the new polls point the momentum meter in McCaskill's direction.

In Ohio, two new polls show Democrat Sherrod Brown leading Republican Sen. Mike DeWine by either 14 percentage points (SurveyUSA) or by six (Rasmussen). Brown's lead on our last-five-poll average (47.6 percent to 41.8 percent) keeps Ohio in the "lean" Democrat column, but the new polls point our momentum meter toward Brown.

In both states, the two automated pollsters show a consistent pattern: SurveyUSA has the Democrat running significantly stronger than Rasmussen. The difference in this case may be that Rasmussen weights—or statistically adjusts—its surveys by party identification (whether voters think of themselves as Democrats or Republicans) while SurveyUSA does not. Recent national surveys show a Democratic bump in party identification, so by setting a fixed mix of self-identified Democrats and Republicans, Rasmussen is either suppressing a real Democratic surge or correcting a momentary spike that will quickly recede (or both). Only time will tell.

Interests disclosed: The internal Democratic Senatorial Campaign Committee survey released in Missouri was conducted by Mark Blumenthal's firm, Bennett, Petts & Blumenthal.

Senate Race Summary for Oct. 12:
The race for the U.S. Senate is looking closer than ever, thanks to a surge for Bob Menendez in New Jersey. Two new surveys out in New Jersey today from Quinnipiac University and Rasmussen Reports show Democratic Sen. Bob Menendez leading Republican Thomas Kean Jr. by margins of four and five percentage points, respectively. Menendez has now run ahead of Kean by at least three points on five of the last six surveys. His four-point lead (45 percent to 41 percent) on our last-five-poll average moves New Jersey to the "lean Democrat" column.

So, as of today, the race for the Senate looks like a dead heat, with 49 seats leaning or held by Democrats and 49 seats leaning or help by Republicans. The two remaining tossups are Tennessee and Missouri.

Speaking of Tennessee, a new Rasmussen poll out late yesterday shows Democrat Harold Ford a statistically insignificant two points ahead of Republican Bob Corker (48 percent to 46 percent). That's the opposite of the SurveyUSA result we noted yesterday, showing Corker ahead by two. Although Ford leads narrowly on our last-five-poll average (46.6 percent to 44.2 percent), his margin remains close enough to classify Tennessee as a tossup.

Senate Race Summary for Oct. 11:
Is it over for Ned Lamont in Connecticut? Another new poll—this one from the Hartford Courant and the University of Connecticut—shows Sen. Joe Lieberman leading by a statistically significant eight points (48 percent to 40 percent). That makes seven straight surveys showing Lieberman running ahead of Lamont, five times beyond the margin of error. Lieberman's lead over Democratic nominee Lamont on our last-five-poll average now tops nine percentage points (48.8 percent to 39.4 percent) and continues to rate Connecticut as "strong" Lieberman.

As the Courant reports, Lieberman's lead comes from winning 67 percent of Republicans, holding on to 35 percent of Democrats, and running ahead of Lamont among independents by a 45 percent to 37 percent margin. Recent polls from Quinnipiac University and Rasmussen Reports show very similar results by party. Remarkably, all three of these polls show Lamont running ahead of Republican nominee Alan Schlesinger—among Republicans. Schlesinger's also-ran status gives Lieberman a tremendous advantage. As long as he continues to hold a third of Democrats, many of whom voted for him in the primary, he will remain the favorite.

Another new poll in Tennessee from SurveyUSA shows another razor thin margin, although this one puts Republican Bob Corker two points ahead of Democrat Harold Ford Jr. While Ford still holds a four-point lead on our last-five-poll average (47 percent to 43 percent), it remains narrow enough to retain the "tossup" rating. The new poll, however, shifts the momentum meter from Democrat to Republican.

Senate Race Summary for Oct. 6:
Rhode Island has gone blue. A new survey from USA Today/Gallup shows Democrat Sheldon Whitehouse leading incumbent Republican Lincoln Chafee by 11 points (50 percent to 39 percent). While Whitehouse's lead in the Gallup poll is much wider than recent polls from Reuters/Zogby (+4) and Mason-Dixon (+1), Whitehouse led (albeit by narrow margins) on every poll conducted since late August. His lead on our last-five-poll average (44.4 percent to 40.0 percent) is now large enough to classify Rhode Island as "lean Democrat."

So, the overall race for control of the Senate has narrowed from a four-seat Republican advantage (50 to 46) a month ago to just a single seat advantage. Right now, 49 seats are held by Republicans or at least lean that way, and 48 seats are held by or lean to Democrats.

The other five statewide surveys released this morning by the Gallup organization have our momentum meters fluttering once again, this time in a predominantly Democratic direction. The new polls moved momentum from Republican to neutral in Missouri and Tennessee, from neutral to Democrat in Maryland and New Jersey, and show a closer margin in Virginia (Allen +3) than the Zogby poll released yesterday (Allen +11).

Senate Race Summary for Oct. 5:
Three new polls in New Jersey with widely varying results explain why we put so much emphasis on averaging polls. Today's results run the gamut, showing Democrat Bob Menendez either leading Republican Tom Kean Jr. by 10 points (Reuters/Zogby), leading by seven points (Fairleigh Dickinson-PublicMind), or trailing by five points (Republican-affiliated Strategic Vision). Random sampling error alone cannot explain the gap. While we could speculate endlessly about the reasons, the simpler approach is to average across polls. Our last-five-poll average continues to show a statistical tossup, with Menendez slightly but not significantly ahead (42.6 percent to 40.6 percent) and no clear momentum to either candidate.

Today also marked the release of 10 new Senate telephone polls from the Reuters/Zogby partnership. Some are consistent with previous surveys, some not so much. In Virginia, Zogby has George Allen up by 11 points (48 percent to 37 percent), a bigger lead than any survey has reported since July, which easily moves the state back to "lean" Republican status and indicates renewed momentum for Allen. Zogby also shows Joe Lieberman leading by 20 points in Connecticut, Mike DeWine and Sherrod Brown deadlocked in Ohio, and Republican Jim Talent in Missouri with a four-point lead. These margins are more favorable to Lieberman, DeWine, and Talent than on any other telephone poll released since Labor Day. While the erratic nature of these results has our momentum meters fluttering in a few states, our overall assessments remain unchanged except for in Virginia.

Senate Race Summary for Oct. 4:
A new Rasmussen automated survey in Connecticut has good news for Joe Lieberman. It shows Lieberman leading Democratic nominee Ned Lamont by 10 points (50 percent to 40 percent). The new poll moves our momentum meter back to neutral. Though previous polls by Quinnipiac and SurveyUSA also gave Lieberman double-digit leads, the three previous Rasmussen surveys conducted since the August primary showed closer margins with Lieberman consistently receiving 45 percent or 46 percent of the vote. Since this new survey has Lieberman at 50 percent, it may indicate some new "Joementum" not yet picked up by our meter. Either way, given his 7.4-point average lead on the last five polls, we continue to rate the race as strong Lieberman.

Senate Race Summary for Oct. 3:
Yes, Virginia, you are now a statistical tossup—barely. A new poll from Rasmussen Reports narrows George Allen's lead on our last-five-poll average to just four percentage points (47.8 percent to 43.8 percent). Three weeks and four surveys ago, Allen's average lead was nearly twice as large (47.8 percent to 40 percent), so the quickening pace of polling has helped move this race to tossup status. But a caution: The latest Rasmussen poll shows Allen leading by six (49 percent to 43 percent). Another comparable result will push Virginia back to lean Republican.

Three new polls in Tennessee leave the Ford-Corker contest looking like a tossup as much as ever. The surveys from Middle Tennessee State University has Republican Bob Corker running one point ahead of Democrat Harold Ford, while new polls from Mason-Dixon and Rasmussen have Ford ahead by one and five points, respectively. The last five polls give Ford an average lead of just under three points (45.2 percent to 42.4 percent) and show no meaningful momentum toward either candidate.

The new Mason-Dixon survey in New Jersey has Democrat Bob Menendez up by three percentage points over Republican Tom Kean Jr. (44 percent to 41 percent). New Jersey remains a tossup, but this new, favorable result for Menendez shifts the momentum meter from Republican to neutral.

Similarly, new polls from Mason-Dixon show razor-thin margins in Missouri and Rhode Island that reaffirm the status of both states as tossups, while moving the momentum arrow in each state from Democrat back to neutral.

Senate Race Summary for Oct. 2:
A new survey in Montana from Mason-Dixon Polling & Research confirms continuing progress for Democrat Jon Tester's challenge to Republican Conrad Burns. The new poll shows Tester running seven points ahead of Burns (47 percent to 40 percent), confirming the similar margin reported by the last Rasmussen survey. Tester now leads by more than five points (48.8 percent to 43.3 percent) on our last-five-poll average. We had already rated this race as lean Democrat, but this new poll confirms continuing momentum in Tester's direction during September.

We also have two new polls in Virginia, one from Mason-Dixon (showing a dead-even race), the other from SurveyUSA (their second in a week, this one showing Republican Sen. George Allen ahead by six). Averaging across all polls indicates a narrow Allen lead—enough to classify Virginia as lean Republican—with no recent momentum to either candidate. The recent stability in this race owes to the power of Allen's repeated gaffes in allowing Democratic challenger Jim Webb to stay close in the face of the incumbent's enormous advantage in television advertising.

Finally, two more new Mason-Dixon polls show the Democratic candidates ahead by a few statistically insignificant points in Ohio and Tennessee, and a new Marist Poll shows Republican Tom Kean Jr. leading Democrat Bob Menendez by five. None of these polls indicates a change in momentum or status. We continue to rate Tennessee and New Jersey as tossups and Ohio as leaning to Democrat Sherrod Brown.

Senate Race Summary for Sept. 29:
Is Bob Menendez back in New Jersey? A new Rutgers-Eagleton poll shows the Democrat one point ahead of Republican Tom Kean Jr. (45 percent to 44 percent). Our momentum arrow indicates Democratic momentum because Kean led by a single point on the last poll and by margins of 3 to 5 points on the three polls before that. But a caution: This most recent Rutgers-Eagleton result is based on just 404 interviews among those they considered most likely to vote. Among the larger subgroup of all registered voters (660 interviews), they showed Kean leading by two points (44 percent to 42 percent). So, our point is that this is still really a tossup.

Senate Race Summary for Sept. 27:
A new SurveyUSA poll in Washington puts Democratic incumbent Maria Cantwell ahead of Republican challenger Mike McGavick by 12 points (54 percent to 42 percent). We rate Washington as "strong" Democrat because of Cantwell's commanding 13.8-point lead on our last-five-poll average. Our momentum meter points in the Republican direction, however, because Republican McGavick's support has been slightly higher on the last two polls than on the previous three.

Senate Race Summary for Sept. 22:
Democrat John Tester is doing well enough in Montana to change our overall vote count. We had judged the race as a tossup. Now we're scoring it as a "lean" for the Democracts, making the overall count 49-47. A new Rasmussen automated poll shows Tester leading Republican Conrad Burns by seven points (50 percent to 43 percent). It confirms the recent momentum shift to Tester and moves Montana into the "lean" Democrat column.

Another new Rasmussen poll in Washington has raised eyebrows in the blogosphere. It shows Democratic Sen. Maria Cantwell's lead over Republican challenger Mike McGavick falling to just six points (48 percent to 42 percent). Previous polls indicated some gains for Cantwell, but this newest reading moves our momentum arrow back to neutral. Because the last-five-poll average shows Cantwell leading by more than 12 points (51.4 percent to 39 percent), we continue to rate Washington as "strong" Democrat.

Finally, a new poll from the University of Minnesota confirms the recent shift in momentum to Democrat Amy Klobuchar over Republican Mark Kennedy. We continue to rate Minnesota "strong" Democrat because Klobuchar's 51.4 percent to 39.8 percent lead on our last-five-poll average.

Senate Race Summary for Sept. 21:
Is Rick Santorum making a comeback? Two new polls in Pennsylvania show Democratic challenger Robert Casey leading the Republican incumbent, but both also show Casey receiving just under 50 percent, which is never good for a candidate in the lead. A new Rasmussen automated poll has Casey leading by 10 points (49 percent to 39 percent), while a new survey from Franklin and Marshall College has Casey ahead by just seven (45 percent to 38 percent). Casey's 11.4 percent lead on our last-five-poll average continues to merit a "strong" Democrat rating, but the narrower margin of today's new polls moves the momentum arrow in Santorum's favor.

In Maryland, a new automated poll from SurveyUSA shows Republican Michael Steele continuing to gain ground in his race with Democrat Ben Cardin. The latest poll shows Steele with a statistically insignificant one-point lead (48 percent to 47 percent). While we continue to rate Maryland as lean Democrat, this new poll shifts the momentum meter in Steele's favor.

For now, Pennsylvania and Maryland are the exceptions. Our national momentum meter continues to point to the Democrats.

Senate Race Summary for Sept. 20:
We've added 14 new Senate polls to the Election Scorecard database since last Friday, yet our overall Senate "momentum meter" continues to point in the Democratic direction. You can see the trend at the state level: Seven states currently indicate recent momentum to the Democratic candidate, while only one (New Jersey) trends toward the Republican. Remarkably, this shift has occurred over the same month in which George W. Bush's approval rating has improved a few percentage points.

In Connecticut, two new polls from American Research Group and Rasmussen both show a closer race than earlier surveys by Quinnipiac, SurveyUSA, and Joe Lieberman's own pollster. Lieberman's lead on our new last-five-poll average narrows to just seven points (47.8 percent to 40.8 percent) and downgrades that race's status from "strong" to "lean" Lieberman.

A Rasmussen automated poll in Maryland narrows Democrat Ben Cardin's lead over Republican Michael Steele just enough to downgrade the race from "strong" to "lean" Democrat. Our last five-poll average now puts Cardin ahead by just over six points (46.2 percent to 40 percent).

Senate Race Summary for Sept. 15:
That sound you hear is our "momentum shift" arrow moving in the Democratic direction. To measure momentum, we average the averages across the 13 states on the scoreboard and look for statistically meaningful change. The shift results from recently improving Democratic fortunes in Tennessee, Virginia, Washington state, Arizona, and, today, Missouri.

In Missouri, two new automated polls from SurveyUSA and Rasmussen show Claire McCaskill running a few points ahead of Republican incumbent Jim Talent, an improvement since late August. Although we continue to rate Missouri a tossup, the momentum arrow now points in McCaskill's direction.

A new Rasmussen survey in Virginia shows Republican Sen. George Allen leading by seven points (50 percent to 43 percent), a slightly wider margin than his lead on the average of the last five polls (47.8 percent to 43.4 percent). This latest survey indicates a leveling off in momentum for Webb over the last five polls.

Senate Race Summary for Sept. 14:
A new SurveyUSA poll from Virginia shows Republican George Allen ahead by only three points (48 percent to 45 percent). This second bad poll for Allen in a week narrows his lead on our five-poll average to just 6.2 points and shifts our classification of this race from "safe" to "lean" Republican. The strong trend to Democrat Webb in the five polls conducted since July leaves the momentum meter pointed in his direction.

Also today, a new poll in New Jersey from Strategic Vision, a Republican-affiliated public-relations firm, shows Republican Tom Kean Jr. running four points ahead of Democrat Robert Menendez (44 percent to 40 percent). The last five-poll average suggests a closer race—Kean leads 41.8 percent to 40.8 percent—so we continue to classify New Jersey as a tossup, with momentum shifting to the Republican.

Senate Race Summary for Sept. 13:
A new SurveyUSA poll in Tennessee shows Democrat Harold Ford leading Republican Bob Corker by three points (48 percent to 45 percent) and brings Ford close enough on our five-poll average to move the race into the tossup column. So, as of today, the number of seats held by Republicans, or leaning that way, falls from 50 to 49.

Today's scorecard also includes a new SurveyUSA poll in Connecticut that shows Joe Lieberman holding a comfortable 51 percent to 38 percent lead over Ned Lamont. The five-poll average is narrower, and the new poll is not different enough to indicate a shift in momentum to Lieberman.

Finally, we have added Maryland to the Scorecard, following Democrat Ben Cardin's victory in last night's primary. Cardin debuts with a seven-point lead over Republican Michael Steele (45.6 percent to 38.6 percent) on our five-poll average, enough to classify the state as solidly Democratic. Our momentum meter for Maryland points in the Republican direction, as the two most recent polls, conducted during August by Rasmussen and Gonzales Research, had Cardin leading by a slightly narrower margin than polls taken earlier in the summer.

Senate Race Summary for Sept. 12:
Only two new Senate polls for our Scorecard: A new Rasmussen automated survey in Washington state confirms the shift in momentum to Democrat Maria Cantwell also seen in two polls from SurveyUSA in late August. The latest survey lifts Cantwell's share of the vote on our five-poll average to 51 percent, giving her a 12-point advantage over Republican challenger Mike McGavick in the wake of disclosures of his 1993 arrest for drunk driving.

In Arizona, Democratic challenger Jim Pederson's campaign released an internal poll showing him gaining on Republican John Kyl at least enough to move our momentum meter in Pederson's direction. We continue to classify Arizona as "safe Republican" due to Kyl's comfortable 14-point margin over Pederson on our last five-poll average. The race remains one to watch at least for now though, because Kyl's support now hovers just below 50 percent.

Senate Race Summary for Sept. 11:
Jim Webb continues to gain ground on GOP Sen. George Allen. A new poll of Virginia from Mason-Dixon Polling & Research shows that Allen leads by just four points (46 percent to 42 percent). This latest survey confirms the shift in momentum to Webb seen on other surveys in recent weeks in the wake of Allen's "macaca" gaffe. While we continue to classify Virginia as "safe" Republican due to Allen's 47.8 percent to 40 percent lead on our five-poll average, keep in mind that the average still includes two pre-"macaca" surveys from July. So, the Virginia race is now likely closer than our scorecard makes it appear.

Since our scorecard includes only surveys based on random probability sampling, it does not include any of the Zogby Interactive/Wall Street Journal polls that were released today. These surveys are conducted on the Internet using samples drawn from a panel of online volunteers. The latest Zogby results for Virginia—showing Webb ahead 50 percent to 43 percent—help explain our caution. Zogby's Virginia samples have been consistently more favorable to Webb than other pollsters, suggesting a bias in Zogby's online methodology.

Senate Race Summary for Sept. 8:
A new Rasmussen automated poll in Tennessee shows Democrat Harold Ford trailing Republican Bob Corker by just one point. That result generally tracks with an internal Ford campaign poll from mid-August that put Ford slightly ahead. Our five-poll average, which includes surveys from July before Ford went on the air with television commercials, still has Corker ahead by five points (45.2 percent to 40.2 percent), so we continue to rate the race as lean Republican, but the momentum arrow is definitely pointing in Ford's direction. Another good poll for Ford could shift this race into the tossup column.

Some caution may be in order. There have been no conventional news-media polls since July, and many pollsters question Rasmussen's use of recorded voices to read poll questions. But as William Saletan observed after the 2004 elections, that approach beat many competitors who used more traditional methods.

Senate Race Summary for Sept. 7:
The latest poll data from the Connecticut race show Joe Lieberman with a whopping big 51 percent to 35 percent lead over opponent Ned Lamont. But, there's a catch. The numbers come from an internal Lieberman campaign poll. Internal polls are not entirely spin (the pollsters who conduct them have a reputation to maintain, so they can't just make up numbers), but they are selectively released by campaigns (you rarely see an internal poll released that shows the candidate losing). We include partisan polls in the Election Scorecard because the five-poll averages smooth out the one-time blips, and that's just what happened here. The momentum arrow for Connecticut remains flat.

Senate Race Summary for Sept. 6:
All is calm on our scorecard today, as the status of all races and the overall momentum indicator remains unchanged. Today did bring a new poll in New Jersey from the automated voice pollster Rasmussen showing Republican nominee Tom Kean Jr. with a five-point lead over Democrat Bob Menendez. It essentially matches a Farleigh Dickinson University poll conducted about the same time that has Kean four points ahead. We rate the race a tossup, as the average of the last five polls shows a dead heat with both candidates at 41 percent. But since the earlier polls in that average had consistently favored Menendez by a few points, our momentum meter for New Jersey is now red, indicating a shift in momentum to Kean.

Senate Race Summary for Sept. 5:
Gallup released surveys in five key Senate races that are now included in our scorecard of five-poll averages. The Gallup result in Pennsylvania showed Democrat Bob Casey Jr. with a much bigger lead among likely voters (56 percent to 38 percent) than in recent polls in that state. The difference was big enough to turn our Pennsylvania momentum arrow in favor of the Democrat from its previous neutral position, indicating a meaningful improvement in Casey's lead over the last five polls.

Senate Race Summary for Sept 1:
Democrats have an uphill fight. Right now, we show 50 seats in the Republican column or leaning that way, 46 seats for or leaning to the Democrats, and four seats in a statistical dead heat. To take control of the Senate, where Dick Cheney breaks the tie, Democrats not only need to take all of those four close races but also one of those races we have in the Republican column.

In recent weeks, Democratic candidates have gained slightly in Ohio, Tennessee, Virginia, and Washington, while Republicans have picked up a few points in Missouri and New Jersey. Most of the states we are tracking, however, have no meaningful change. Since the net shifts at the state level have been largely offsetting our overall momentum shift, all of the races begin in the "no advantage" position, with no visible national trend helping either party. (Click here for an explanation on how to read the race details.)

Just to review: To gain a majority, Democrats must hold all of their 44 seats and pick up seven now represented by Republicans. We show Democrats currently leading in two Republican states (Pennsylvania and Ohio) but in tossup races in three more (Missouri, Montana, and Rhode Island). One state now held by a Democrat—New Jersey—is currently a statistical tossup.