Gore advisers all but ruled out a presidential bid for the former Vice-President, saying that

"he definitely has the ambition to use the peace prize as a springboard to run for president.

But he will not run, because he won't take on the political machine assembled by Sen. Hillary Clinton, said the source. If the senator from New York had faltered at all, Gore would take a serious look at entering the race, the source said. But Gore has calculated that Clinton is unstoppable, according to the source."

And why is Hillary unstoppable? Josh Marshall said it best earlier in the week:

Obama isn't so much running for the nomination in the sense of reaching out and taking it. He's trying to show us how marvelous he is (and this isn't snark, he's really pretty marvelous) so that Democratic voters will recognize it and give him the nomination.

But that's not how it works in this country. I don't know if it really works otherwise anywhere else. But you have to really want it, come out and say it, take it.

If this were a different race, Gore would step right in. Its not. I expect him to stay out.