It will be a nutty night. What to look for.

The story lines for America's first seminational primary day extend, literally, from one end of the continent to the other. (Can Barack Obama catch Hillary Clinton in Connecticut? Can Ron Paul's libertarian message actually produce a victory in the Alaska caucuses?) Here's what's to watch for, starting with the Republicans.

The Republicans

Giuliani made them, McCain will take them: Back last year, when Rudy Giuliani was riding high in the national polls, his supporters pulled off a tactically shrewd series of rules changes in the Northeast. New York, New Jersey, and Connecticut all became "winner-take-all" states; a candidate who got one vote more than the next contender won all the state's delegates. (The Democrats banned this approach after the tumultuous 1972 Democratic convention fight over whether California could keep that system—the fight that ensured the nomination of George McGovern.)

Even before Giuliani dropped out of the race, John McCain had taken the lead from him in all three of these Northeast states. Now, barring a McCain appearance at a Black Mass (and given New York's approach to matters spiritual, maybe not even then), McCain appears certain to win New York—and its neighbors. Throw in two other winner-take-all states—Delaware, and his home state of Arizona—and McCain seems highly likely to pick up more than 250 delegates on Tuesday night, without breaking a sweat. This is more than 20 percent of the total he needs for the nomination. Romney, by contrast, can count on only Utah and its 36 delegates. That leaves one winner-take-all primary state where the outcome is uncertain …

Missouri and Georgia, bigger than they oughta be: It's not just that all 58 of Missouri's delegates will go to the winner. It's that, thanks to the Republican Party's rules, Missouri is supersized. Because states that voted for Bush in 2004 get a bonus, Missouri will have more delegates than the bluer state of New Jersey, even though New Jersey has almost 3 million more people in it. Mitt Romney almost has to win this "Show Me" State if he wants the race to continue in the coming weeks. He faces two problems: First, the Missouri primary isn't restricted to Republican voters, and McCain always does better with independents. Second, Mike Huckabee is more or less competitive here, especially along the southern tier that borders his home state of Arkansas, where religious conservatives and rural voters abound. (It's where you'll find Branson, a town devoted almost wholly to country music.)

Another problem for Romney: Georgia (population 9.3 million) is choosing 72 delegates. (This is more evidence of imbalance: Illinois, population 12.8 million, gets only 70.) Georgia is by far the biggest Southern state, and here Mike Huckabee may be proving to be John McCain's best friend outside the press. Polls suggest a three-man race; it's a highly reasonable inference that without Huckabee, Romney would be winning Georgia in a walk.

California, here he comes: If you want to know why Mitt Romney is crossing the continent to spend the last day before Super Tuesday in California, just check out the polls. He's got a real shot to win that state. If the enthusiastic backing that Gov. Arnold Schwarzenegger is giving McCain leads you to ask how this could be, take a closer look at the California Republicans. Arnold aside, the party much more reflects the outlook of House Republicans like Wally Herger (Americans for Democratic Action rating: 0); John Doolittle (League of Conservation Voters rating: 0); and George Radanovich (Family Research Council rating: 100). Indeed, it's not too much to say that Arnold got into the statehouse because he never had to compete in a GOP primary. Throw in the fact that only Republicans can vote on Tuesday, and it's more than possible that Romney could pull off an upset.

If Romney wins here, it might not mean that much for the delegate count. The California GOP awards only 11 delegates to the statewide winner; the others are chosen by congressional district—and whoever wins the district gets all three delegates. But with McCain holding commanding leads in every national poll, a victory in the biggest state would give Romney a rationale to keep writing checks to himself.