JIM LEHRER: And tonight in Iowa, it finally begins: the contests and the voting that will eventually lead to the election of the next president of the United States.
Some 150,000 Democrats, 90,000 Republicans were expected to caucus this evening in Iowa. Among Democrats, a final tracking poll had Senator Barack Obama up 4 points over former Senator John Edwards, with Senator Hillary Clinton running third.
On the Republican side, former Arkansas Governor Mike Huckabee was 6 points ahead of former Massachusetts Governor Mitt Romney. Candidates on both sides called the race a toss-up.
Judy Woodruff has more on the day's final lead-up events.
FORMER GOV. MIKE HUCKABEE (R), Arkansas: You know, it's kind of almost frightening, but six hours from now, the doors open.
JUDY WOODRUFF: It's a day that's been circled on political calendars for months, and there was still time today to rally supporters.
ANNOUNCER: The next president of the United States, John Edwards!
JUDY WOODRUFF: In the Democratic race, John Edwards told steelworkers in Des Moines that he was confident his message would resonate.
FORMER SEN. JOHN EDWARDS (D), Presidential Candidate: Two campaigns believe that their money would make them inevitable. But tonight, Iowa caucus-goers are going to prove that our campaign to stand up for the middle class and to stop corporate greed in America is unstoppable.
JUDY WOODRUFF: Barack Obama made the rounds on morning talk shows and talked optimistically.
SEN. BARACK OBAMA (D), Illinois: We feel good about what we've done, but this is the beginning, and not the end. And so our goal is just to do well tonight. We think we will.
JUDY WOODRUFF: Obama had no public events. Instead, like most of his competitors, he put his fate in the hands of precinct captains, Iowans like Maeve Callan, whom we found in her kitchen, baking cookies and putting the finishing touches on arrangements to get supporters of her candidate to stand in his corner at the caucus tonight.
MAEVE CALLAN, Obama Precinct Captain: It basically comes down to transportation and childcare. Those are the two main things. And we've arranged for that. My husband will be going around, picking up people who aren't comfortable driving at night. You know, we're having babysitters for other people who need childcare.
JUDY WOODRUFF: Hillary Clinton also suspended campaigning today, but she did appear on the "CBS Morning Show."
SEN. HILLARY CLINTON (D), New York: You know, I'm running against two people who have been really working Iowa very hard for a long time, one for four years, one from a neighboring state. But I feel good about what we've been able to do.
JUDY WOODRUFF: The Republican contest, meanwhile, was focused mainly on two candidates. Mike Huckabee started his day in Burlington.
MIKE HUCKABEE: I'm very optimistic and hopeful that we're going to have an incredible day, an incredible night, an incredible launch to the White House, and it will all have started right here in Iowa.
JUDY WOODRUFF: By contrast, Mitt Romney tempered expectations, both for Iowa and New Hampshire.
FORMER GOV. MITT ROMNEY (R), Massachusetts: I'm in a good spot in both of these two states. I'd like to win them, but if I don't win, coming in second in these states is a strong statement.
JUDY WOODRUFF: John McCain and Fred Thompson angled for third place. Thompson denied reports he would drop out if he finishes worse than that.