Andrew Sullivan makes much of this “caveat” at Slate — which now says the election would go to Bush if held today:
Here is the math that matters: If all the states in which the data lean discernibly to either candidate vote as the polls suggest, the election will come down to Florida and Ohio. If Bush takes both, he wins. If Kerry takes either, he wins. We assess the probability in each state independently, and we assume that neither state’s turnout affects the other’s. Since the odds in each of the two states are approximately 50-50, with a tiny edge to Bush, the combined probability of Kerry winning the election is about 70 to 75 percent.
I suppose this is all true. But someone should make clear to Andrew that it’s all true only if Kerry wins Wisconsin (and several other swing states). In other words the probability is 70 to 75 percent if Kerry’s 100% sure to win Wisconsin. If Kerry doesn’t win Wisconsin than even if Kerry wins Ohio or Florida he still loses. Indeed, if the race boils down to the slate scenario Kerry loses if any of Slate’s Kerry states go the other way, including not only the biggies like Ohio but also New Hampshire or Hawaii.