Read the whole thing, but this is a very interesting point:

A final point – the exit polling data offers some counter-intuitive evidence about who is being helped by the conduct of the Iraq war. In New Hampshire, Romney won voters who approve of the conduct of the Iraq war, 37% to 33%. McCain won those who disapprove, 36% to 29%. The results were roughly the same in Michigan. Romney won approvers 42% to 27%. McCain won disapprovers 36% to 29%. These results are, I think, a blow to the idea that McCain did so well in New Hampshire because of the surge in force levels. They also may foretell trouble for McCain in South Carolina – even though he was an early and strong supporter of the surge, he does not seem to be getting a great deal of credit for it.

ME: Although these results are probably more an indication that conservatives–the strongest supporters of the war–aren’t enthusiastic about McCain than anything else.