To be taken as a serious challenger to Mitt Romney for the Republican nomination, a candidate has to finish ahead of Ron Paul in the Ames Straw Poll. This may be a high standard to meet, since Paul is going all out in Iowa to try to win the straw poll. He paid $31,000 to get the prime location beside the entrance to the polling place (the same location Romney had in 2007), and his campaign is funding $20 of the $30 price of tickets for all Ron Paul voters.
With Romney on the sidelines, the winner of the Ames Straw Poll will claim the mantle of the anti-Romney candidate. In addition to Paul, only Bachmann, Cain, McCotter, Pawlenty and Santorum have decided to compete actively in Ames by purchasing tent space and the right to speak at the event. Gingrich apparently couldn't come up with the $15,000 entry fee (the Iowa Republican Party doesn't extend credit), joining Huntsman and Johnson as candidates who will be on the outside looking in.
Bachmann is predicted to win Ames. If she comes in 2nd, her campaign will take a serious body blow. If she loses to Ron Paul, her campaign will be seen as a flash in the pan and voters will move on to "the next best thing". Cain and Pawlenty (who both used to be "the next best thing") have the most to both gain or lose. If either finishes behind Ron Paul, they will join Gingrich and Johnson on the list of campaigns that are goners. Santorum and McCotter will almost surely lose to Paul and will be out of the race and off the podium in future debates. If either does finish ahead of Paul, it will be the "Big Story" coming out of Ames.
Rick Perry's supporters are making noises about launching a last minute effort to compete in Ames, which could cause serious damage to a Perry campaign if he doesn't beat fellow Texan, Ron Paul. This would be a big gamble for a flegling Perry campaign. Best for him to sit this one out and let Ron Paul narrow the field for him. If he does announce his candidacy before Ames and decide to go "all in", he could become the "Big Story" simply by beating Paul. He doesn't really have to beat Bachmann, Pawlenty or Cain in Ames, just Ron Paul.
There is, of course, always the possibility that Ron Paul will win the Ames Straw Poll--he does well in straw polls. The big winner in that event will be Mitt Romney. Don't be surprised that some Romney supporters will in fact put in votes for Paul, just to take out the "serious" opponents. A Paul win will turn the race on its head and will surely bring Sarah Palin and Rudy Giuliani in as candidates.
One thing is for sure, the Ames Straw Poll always adds drama to the campaign. Expect the same this year. There will be winners, losers, and Ron Paul.