We asked PostOpinions columnists, bloggers and editors who would win Tuesday night’s Iowa caucuses and why. Read all the PostOpinions predictions, as well as analysis of Iowa from Michael Gerson, Kathleen Parker, Eugene Robinson, Jennifer Rubin and Marc Thiessen.

The runner-up will be Rick Santorum. He has come from literally nowhere – five percent as late as October – to 15 percent this last week. He’s an impassioned social conservative – neither Romney nor Paul is believable on that score – and moreover, he has not been damaged by the campaign. He came in as a bullet-proof social conservative and he’s going out as one. If Michele Bachmann’s supporters figure – quite rightly – that a vote for her is a waste of time and energy – then Santorum is where they will go.

Ron Paul comes in third. In the most recent poll, he got 22 percent, but he’s apparently peaked at that number and is headed earthward. Still, his constituency is a fervid one and it will not desert him just because he makes no sense whatsoever. Paul gets the show position.

Rick Perry will come in fourth. He will get the votes of some social conservative who think Santorum hasn’t a chance in the general election and anti-Romney people who think that only Perry has the money to stop him.  My algorithm finds no one who will vote for Perry for his own virtues.  

Fifth place goes to Newt Gingrich. In November he got 25 percent in the Register poll, but since then Newt Gingrich has been exposed as Newt Gingrich — virtually a calumny — and his numbers plummeted to 12 percent. They are undoubtedly lower now.

Michele Bachmann will come in last with about 5 percent of the caucus. These five percent will vote for her because there is no accounting for what some people do. This, too, is in my algorithm.

The Iowa caucus has turned out to be a demolition derby for Republicans. With the exception of Romney and Santorum, they all have been damaged. Perry showed he couldn’t debate (or talk), Bachmann had trouble with the truth, Gingrich acts like R2-D2 with a short circuit and Paul has been soiled by the ugly newsletters his foundation published in the past. Santorum emerges undented, (al dente?) but that could be because until too late he was not considered worth denting. Aside from him, though, only Romney came out of Iowa as he came in – boring, but inevitable. He wins because everyone else loses.