I'll remember McCain throwing quote marks around the words "health of the woman", and then sneering, as if the health of women isn't worth his time. I was talking to my significant other during the debate, toking a bowl, and she said, "Waitaminute, did he really just say what I think he did?" We scrolled back and replayed it, and sure enough, there was McCain mocking the health of women.
Seeing as women are the largest voting population (and largest overall population), of the two sexes, he really REALLY hurt himself there. If the election had been close before that point, he would have lost it right there. He's lost it anyway, but that mockery would have sealed the deal for an Obama win even if it were a closer race.