Bloggers are previewing Tuesday's Pennsylvania primary and watching some inter-blogosphere mudslinging.

Keystone primary: Various polls show Hillary Clinton winning Pennsylvania on Tuesday by anywhere from five to 13 points. Public Policy Polling has Barack Obama ahead by three. Could a Keystone upset be in order?

No, says Geekesque at DailKos: "Once again we see Obamanation getting their expectations out of whack. ... Obama will not break 45% on Tuesday. He may not break 43%. So, the question is, are Obama supporters stupid enough to irrationally fuel expectations to give Clinton the appearance of another moral victory and defeat of expectations--thus handing a media win to her?" Sluicing the poll data at First Read, Chuck Todd notes that those blue-collar voters Obama offended are leaning toward Clinton. "She's up 54-33 among bowlers and 53-28 among gun owners; There were 13% undec. among bowlers and 17% undec. among gun owners. So while the poll shows Clinton with a narrow lead (and arguably a narrowing lead), the clues inside the numbers indicate this is her race to lose and that her lead could expand."

But while 10^th-frame turnout among heat-packing bowlers will help Hillary, a report in Politico indicates she'd be better off if the vast numbers of newly registered voters stay home. Of the 217,000 newly registered voters and 178,000 party-switchers since January, "Obama was the preferred candidate for 62 percent of them."

Either way, according to Clive Crook, Obama's notorious "bitter" diatribe won't figure: "The Democratic voters most likely to be offended by Mr Obama's sympathetic account of their errors are the white working class and they were backing Mrs Clinton anyway." Nevertheless, Slate's Mickey Kaus discusses four ways to solve the "condescension conundrum" that could affect Obama in the general election. 

But how big must Clinton win to stay alive in the race? "A 25-point victory in Pennsylvania, plus 20-point wins in later contests in West Virginia, Kentucky and Puerto Rico," according to a much-discussed Bloomberg report. Wonkette has already listed 10 reasons why it's over for Hillary. They include: Her need to win 65 percent of the remaining delegates to break even, her record-low character ratings, and her failure to achieve the endorsement of Robert Reich.

At Reason, David Weigel tries to predict the prospective concession speech. "Two months from now, if Clinton cuts bait and leaves the race with the same 100-odd delegate deficit she's had since February, I wonder what we'll say the point of the long primary was," he writes at Hit & Run. "Vetting Obama? Full employment for political journalists? Ad revenue for local TV stations?"   

Read more about the Pennsylvania primary. In Slate, read John Dickerson's dispatches from the trail here and here. Cynthia Baughman tries to figure out if Pennsylvania delegates can change their mind. And Tim Noah wonders why Hillary Clinton has not denounced or rejected her endorsement from the man behind the vast right-wing conspiracy.

Life imitates South Park: A real-life Kyle-Cartman spat has emerged in the aftermath of Bill Kristol's New York Times column questioning Obama's faith by comparing his "bitter" comments to a statement by Karl Marx that "religious suffering is at the same time an expression of real suffering and a protest against real suffering. Religion is the sigh of the oppressed creature, the sentiment of a heartless world, and the soul of a soulless condition. It is the opium of the people." The New Republic's Leon Wieseltier and former TNR editor Andrew Sullivan are duking it out.

"A non-Christian manipulator of Christianity is calling a Christian a liar about his own faith," wroteSullivan in response to Kristol. That sentence didn't pass over Sullivan's former colleague Wieseltier. "Ponder that early adjective," he wrote at the New Republic. "It is Jew baiting. ... If Kristol is wrong about Obama, it is not because Kristol is a Jew. So this fills me with a certain paschal wrath. Nice little blog you have there, Obama boy. Pity if frogs or locusts should happen to it. Let my people be!"