The other thing I think is neglected: McCain was, throughout the GOP primary season, the only Republican who polled with ten of Obama.  Taking the myth of McCain the Maverick -- and don't forget that everything must be good news for John McCain -- and the fact that most Americans at least had some idea of who McCain was (while 70% of the country hadn't even heard of Obama until the primaries ramped up), I think it makes some sense.

McCain was the only one who had a prayer of not being completely humiliated.  Romney polled about 15 points behind Obama.  Huckabee polled about the same.

Conservatives want live babies so they can raise them to be dead soldiers. - George Carlin