Republican Polling Data on Iraq

From Daniel Larison:

Some interesting crosstab data from a recent Rasmussen poll on the question of withdrawal of combat troops from Iraq. 59% of all Americans favour withdrawal either immediately or within a year, including 39% of Republicans. How is it possible that almost four out of every ten Republicans want out of Iraq, and yet the one candidate who promises to do just that receives virtually no support in polling?

The first that comes to mind is that GOP primary polls focus on "likely Republican voters," who would likely be die-hards and more likely to tow the party line, as opposed to people who just identify with the party. But that all depends on how the poll is being taken and by whom. The implication, of course, is that Paul could receive a surprise wellspring of support come election day, but this would depend on what priority GOP voters use the war to determine the candidate they support. I don't know how that will translate during the caucuses in Iowa (where Paul is polling between 1% and 4%), but that may turn into unexpected support in New Hampshire.