Romney got 25% in Iowa last time so it’s not surprising to me he’s getting about the same. The fact that he still can’t get above that level after all this campaigning is kind of damning, I think. I don’t think the electorate has changed, but the social conservative vote is fragmented, so it can’t get up to 35% on one candidate like it did with Huckabee.
http://en.wikipedia.org/wiki/Iowa_Republican_caucuses,_2008
Delegates are being given out proportionally, different from last time, so this is not a winner-take-all. If the vote is close, the winner walks away with barely more delegates than the 2nd or 3rd person. What I am unsure about is whether one candidate can drop out of the race and “give” their delegates to another candidate.
Its a caucus so the “voters” have a chance to evaluate how many votes the other candidates are getting and change their votes. There is a good chance that voters will coalesce around a single not Romney candidate.