Here's a 1,000-person poll on 2008 presidential prospects.
On the Republican side, McCain (28), Giuliani (22) and Rice (13) are the leaders, with Gov. Mike Huckabee way down the list with a 1. It is very early, of course. And remember what Iowa, where Huckabee has been raising money for Republican legislators, did for John Kerry. (To Democrats' resulting dismay.)
Hillary, of course, leads Democratic contenders.
UPDATE: Rasmussen also has some presidential polling out testing Barack Obama's popularity. He'd lose to McCain and Giuliani in this sample, but -- local angle -- he'd beat Mike Huckabee 50-31.