While channel surfing very early this morning, I dwelled for a moment at Fox, and heard the usual cawing about the presidential race tightening. But unless I'm mistaken, the pre-spin there seemed half-hearted, as did the talk about an obscure Obama relative living in the country illegally.

We're now finally at the point where polls have told us everything they have to say, and here's Nate Silver's assessment as of 3:00 a.m. today:

McCain's clock has simply run out. While there is arguable evidence of a small tightening, there is no evidence of a dramatic tightening of the sort he would need to make Tuesday night interesting.

Related to this is the fact that there are now very, very few true undecideds left in this race. After accounting for a third-party vote, which looks as though it will come in at an aggregate of 2 percent or so...I am showing only about 2.7 percent of the electorate left to allocate between the two major-party candidates. Even if John McCain were to win 70 perecnt of the remaining undecideds (which I don't think is likely), that would only be worth a net of about a point for him. Frankly, McCain's winning scenarios mainly involve the polls having been wrong in the first place -- because of a Bradley Effect or something else. It is unlikely that the polls will "tighten" substantially further -- especially when Obama already has over 50 percent of the vote.

When it comes to the state-by-state contests, the situation is even clearer. All of the states that seem to be close at the end of this campaign--FL, MO, OH, NV, NC, IN and VA--are states that John McCain must carry. But even if he carries them all, he still loses.

To sum it all up, if McCain somehow wins, it will produce the largest demolition of the public opinion research profession since Dewey and Truman 60 years ago--perhaps even larger, since the two national pollsters of that era didn't bother to test opinion during the last week in 1948.