Kerry seriously kicked Bush's ass in the 2004 debates, but the sheeple voted for Bush anyways. The first debate looked like a debate between an incumbent President Kerry and some random guy named Bush that was picked up off the street.
The third debate I have to admit Bush did well, I assume that part helped him put him up at even levels with Kerry.
They were many factors I can go all say on why Bush won, but if Obama does do well in all 3 no matter what he will win.
And if Obama does as poorly in any of the three as Bush did in the first debate, he's a total one-termer.