Jan. 27 (Bloomberg) -- Barack Obama won South Carolina's Democratic primary by a more than 2-to-1 margin over Hillary Clinton, giving his campaign a burst of momentum 10 days before the biggest voting day of the 2008 presidential race.

The Illinois senator, 46, an African-American, got 55 percent of the vote to New York Senator Clinton's 27 percent, with overwhelming support from black voters, who made up half of the record number who cast ballots. Former North Carolina Senator John Edwards placed third with 18 percent.

Obama, as he looks toward competing in more than 20 states on Feb. 5, said he was leading ``the most diverse coalition of Americans that we've seen in a long, long time'' and he sought to close the racial divisions opened during the campaign.

``I did not travel around this state over the last year and see a white South Carolina or a black South Carolina,'' Obama told a cheering crowd of supporters last night in Columbia, South Carolina. ``I saw South Carolina.''

Clinton, 60, who won the last two contests in New Hampshire and Nevada, congratulated Obama last night while speaking to voters in Nashville, Tennessee. She said the country now turns to Feb. 5, when ``millions and millions of Americans are going to have the chance to have their voices heard.''

Edwards, who was born in South Carolina, had been looking to the state to revive a campaign overshadowed by the battle between Clinton and Obama. Speaking to supporters in Columbia last night, he vowed to stay in the race.

Turnout

More than 532,000 people cast ballots yesterday in a state that hasn't voted for the Democrat in the presidential general election in three decades. That is almost double the number who voted in the 2004 primary and 100,000 more than voted in the Republican contest a week earlier.

The victory in South Carolina adds to Obama's earlier win in largely white, rural Iowa, and he will now try to use it as he and the other Democratic candidates focus on 22 states holding nominating contests on Feb. 5, including California, New York and Illinois as well as several Southern states.

``A lot of voters will be taking a second look at him,'' said Merle Black, a political scientist at Emory University in Atlanta. ``He could do quite well in the Super Tuesday races.''

Obama carried 81 percent of the black vote to Clinton's 17 percent and got about a quarter of the white vote, trailing Clinton and Edwards, according to exit polls cited by Fox News, CNN and MSNBC. Polls cited by MSNBC found that Obama won half of the state's young voters, aged 18 to 29.

Criticism

Both Clinton and her husband, former President Bill Clinton, drew criticism in the past few weeks from black leaders who said they had injected the issue of race into the campaign. Obama accused Bill Clinton, who has enjoyed strong support among black voters, of making statements that ``aren't supported by the facts.''

The former president also drew fire yesterday by comparing Obama's South Carolina victory to that of another black politician who won the state's Democratic presidential primaries in 1984 and 1988. ``Jesse Jackson won South Carolina twice,'' Clinton said, according to the New York Times.

Obama today declined to criticize Bill Clinton. ``But there is no doubt that I think that in the '90s, we got caught up in a slash-and-burn politics that the American people are weary of,'' Obama said on ABC's ``This Week'' program. He added that it was ``not the Clintons' fault.''

Husband's Role

Hillary Clinton defended her husband's role in her presidential campaign on CBS's ``Face the Nation'' program today. She cited sleep deprivation for his ``passionate and vigorous'' defense of her candidacy, while acknowledging that all of the spouses have ``maybe got a little carried away.''

``He is going to continue to be with me and support me and speak out for me,'' said Clinton. ``I'm really glad that he's there with me, and I think everybody just needs to take a deep breath,'' she said.

The results in South Carolina amount to a ``huge repudiation'' of the Clinton campaign's tactics and she may have difficulty drawing support from black voters going forward, Black said.

Without mentioning her by name, Obama last night chided Clinton for attacks on him that 70 percent of South Carolina voters said were unfair, according to exit polls.

`Say Anything'

``We are up against the idea that it's acceptable to say anything and do anything to win an election,'' he said. ``We are not just up against the ingrained and destructive habits of Washington, we are also struggling against our own doubts, our own fears and our own cynicism.''

South Carolina has 54 Democratic delegates to the Democratic nominating convention, including 45 awarded to the candidates based on yesterday's results. The Obama campaign said it expected to win 25 delegates in the state, compared with 12 for Clinton and 8 for Edwards. A Democrat needs 2,025 delegates to win the nomination.

Florida holds the next primary on Jan. 29, though it will be a largely symbolic contest. The national Democratic Party stripped the state of its delegates as punishment for moving up its primary, and the candidates pledged not to campaign there. There are 1,681 delegates at stake on Feb. 5.

``A big win by one of candidates on Super Duper Tuesday could at least provide some clarity,'' said Barry Burden, a political science professor at the University of Wisconsin in Madison. ``So far it's been a split decision.''

To contact the reporters on this story: James Rowley in Washington at jarowley@bloomberg.net; Kristin Jensen in Washington at kjensen@bloomberg.net

Last Updated: January 27, 2008 14:44 EST