An AP survey estimates that 40% of Republican primary voters (and 20% of Democratic voters) have switched their allegiances since November.

The AP bases its conclusions on interviews with the same, 2000-person national sample.

Other findings:

## Half of the sample still doesn't know enough about Mike Huckabee to know whether they like him or not, which is a fairly strong confirmation of the hypothesis that he's running a very narrow campaign. More than 50% of white evangelicals switched candidates, and more than 60% of the switchers chose Huckabee.

## Fred Thompson's support in the sample has been cut in half.

## 20% of Republicans who insisted they wouldn't change their minds did so anyway -- and only a third of Democrats who said they probably would change their minds did.

## Republicans who tend to be more concerned about corruption were more likely to shift away from Rudy Giuliani.

## 6 In 10 supporters of Obama and 6 in 10 supporters of Clinton say they've made up their minds and won't change.