McCain picked Palin for one reason (and it's a stupid one at that):

McCain and the Republican Party seriously think a woman on the ticket, ANY woman, will get the irate Hillary-supporter holdouts.

Well, forget for the moment that there are probably precious few of those left. I think CNN brought back the same woman (who said she still loves Hillary and Obama hasn't sold her yet) about ten times... and even SHE said she wouldn't vote for McCain, but just wasn't sure whether she'd vote for Obama.

Forget the fact that the controversy was played to the hilt by the media, and wasn't nearly as dire as it seemed.

What McCain doesn't realize is that the hardcore Hillary supporters, the ones who felt dejected and angry about the primaries, are also hardcore Democrats. They are also not all women, nor were they all supporting Hillary simply because she is a woman. There's no way in hell any significant percentage of them are going to vote for McCain.

Any tiny gain he may get from those voters, as well as a likely larger gain he may get just from some moderates who would like to vote for a woman, will be far outweighed by the negatives she brings to the ticket (not the least of which is instantly undercutting his most potent argument against Obama: experience). And moderate women are mostly pro-choice, so there goes most of that vote.

Most of the votes he will get from Palin were people who were going to vote McCain anyway.