The Republican race is in an enormous state of flux, with three top-tier candidates running three very different campaigns. The candidates are beginning to sense that they have, at most, three or four weeks to break out of their shells.

These rankings are ordered by likelihood of winning the Republican primary and are based on a number of factors, including organization, money, buzz and polling. Click here for Democratic rankings.

1. Rudy Giuliani -- He became serious about New Hampshire at the very moment Mitt Romney began to close the deal. Expectations for the national front-runner ought to be high in at least one of the two early states. What about Iowa? Second place seems up for grabs but organizationally, the campaign is very behind in that state. And then there's Michigan; what's the campaign going to do there? His first round of TV ads will tell us the early state strategy... maybe.

2. Mitt Romney -- Romney's on cruise control through the Iowa caucuses, where he's expected to win, and in New Hampshire, where he isn't. He's in real trouble in South Carolina. But Michigan is turning into a great opportunity for Romney to rebound should he narrowly lose in New Hampshire. If he wins two of the first three and then loses South Carolina, it's a long campaign, with March's Junior Tuesday (not February's Tsunami Tuesday) being the decisive primary day.

3. Fred Thompson -- Thompson survived "Meet The Press" with only minimal fodder for his opponents. He's getting more comfortable taking up the space McCain used to occupy. He wants to be the sober, serious guy.

Continue reading our 2008 Race Rankings.

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