As Joe notes below, much of the buzz around that eye-popping Des Moines Register poll, with its big lead for Obama, centers on the question of how many non-Democrats (independents and Republicans) will be voting in the Iowa Democratic caucuses. The Register poll suggests that 45% of Democratic caucusgoers will not be Democrats. That would mark a dramatic change from past caucuses, and the Register may in fact be on to something that tells us a lot about how different this election year will be.
However, campaign officials here on the Hillary Clinton bus, which is rolling between Ames and Des Moines as I type this, note that if you look at the Register’s numbers for Democrats, their candidate leads by six points. And if you assume the turnout pattern looks like it did in 2004, with 80% of caucusgoers being Democrats, she still wins by two points.
Has Barack Obama really succeeded in created a new kind of coaltion in Iowa politics? That is looking more and more like the question that will determine who wins on Thursday.