Just how ugly is the electoral map for McCain? He is favored right now to win 174 electoral votes. He needs 270. That means, obviously, he's 96 votes shy. FL, where he trails, would be 27 of them. 69 more. Let's say NC (15) and MO (11), both states where he is currently trailing, give up their flirtation with sanity and slouch back to the doddering arms of the GOP. 43 more. Ohio (20 EV), where he also trails, decides to forget about all that unemployment stuff, cling to its guns and religion some more, and vote for the old guy with the crazy-but-hot woman sidekick. We've winnowed it down to 23. Pennsylvania (21), which has voted for the Blue guy four times in a row, and where Obama is up about 10 points in the polls, decides it's boring, and votes Red for a not-change. 2 EV left. He could pick those up with NH (3), or NM (5), or hell, any state to get himself over the top -- as if his campaign could possibly be any more over the top.
If you were to crunch the numbers using polls and probability calculations, the odds of this happening are pretty remote, maybe 1/100, 1/120 or so from a quick eyeball of the data. It just won't happen. He needs an exogenous event -- something entirely outside the current calculations -- to shake things up. Obviously, if something happens that allows McCain to win PA, winning FL, and NC, and VA, etc won't be a problem. But he needs that event. Maybe Osama will lend a hand.