Obama just delivered this speech in Des Moines, Iowa...

The Washington Post's Eugene Robinson calls it "a goosebumps moment"...

The Atlantic's Matt Yglesias called it "Electrifying. Exciting"...

The American Prospect's Ezra Klein writes...

Obama's finest speeches do not excite... They elevate. They enmesh you in a grander moment, as if history has stopped flowing passively by, and, just for an instant, contracted around you, made you aware of its presence, and your role in it. 

UPDATE: The New York Times' David Brooks writes...

Barack Obama has won the Iowa caucuses. You’d have to have a heart of stone not to feel moved by this. An African-American man wins a closely fought campaign in a pivotal state. He beats two strong opponents, including the mighty Clinton machine. He does it in a system that favors rural voters. He does it by getting young voters to come out to the caucuses.

This is a huge moment. It’s one of those times when a movement that seemed ethereal and idealistic became a reality and took on political substance.

Iowa won’t settle the race, but the rest of the primary season is going to be colored by the glow of this result. Whatever their political affiliations, Americans are going to feel good about the Obama victory, which is a story of youth, possibility and unity through diversity — the primordial themes of the American experience.

And Americans are not going to want to see this stopped. When an African-American man is leading a juggernaut to the White House, do you want to be the one to stand up and say No?

Obama has achieved something remarkable. At first blush, his speeches are abstract, secular sermons of personal uplift — filled with disquisitions on the nature of hope and the contours of change.

He talks about erasing old categories like red and blue (and implicitly, black and white) and replacing them with new categories, of which the most important are new and old. He seems at first more preoccupied with changing thinking than changing legislation.

Yet over the course of his speeches and over the course of this campaign, he has persuaded many Iowans that there is substance here as well. He built a great organization and produced a tangible victory.

UPDATE II: AP...

DES MOINES, Iowa (AP) - A victorious Barack Obama portrayed his decisive first-place finish in the Iowa Democratic caucuses as a "defining moment" that he said would lead the way to change in Washington and an end to the war in Iraq.

The first-term senator from Illinois promised "a nation less divided and more united" and told those at a victory rally they could some day "look back and say this is the moment where it all began.