COLUMBIA, S.C. -- Barack Obama routed Hillary Rodham Clinton in the racially-charged South Carolina primary Saturday night, regaining campaign momentum in the prelude to a Feb. 5 coast-to-coast competition for more than 1,600 Democratic National Convention delegates.
Former Sen. John Edwards of North Carolina was running third, a sharp setback in the state where he was born and scored a primary victory in his first presidential campaign four years ago.
The Associated Press made its call based on surveys of voters as they left the polls.
About half the voters were black, according to polling place interviews, and four out of five supported Obama. Black women turned out in particularly large numbers. Clinton and Edwards each won roughly 40 percent of the white vote, with about 25 percent going to Obama, the first-term Illinois senator.
The victory was Obama's first since he won the kick-off Iowa caucuses on Jan. 3. Clinton, a New York senator and former first lady, scored an upset in the New Hampshire primary a few days later. They split the Nevada caucuses, she winning the turnout race, he gaining a one-delegate margin. In a historic race, she hopes to become the first woman to occupy the White House, and Obama is the strongest black contender in history.
The South Carolina primary marked the end of the first phase of the campaign for the Democratic presidential nomination, a series of single-state contests that winnowed the field, conferred co-front-runner status on Clinton and Obama but had relatively few delegates at stake.
That all changes in 10 days' time, when New York, Illinois and California are among the 15 states holding primaries in a virtual nationwide primary. Another seven states and American Samoa will hold Democratic caucuses on the same day.
All three contenders campaigned in South Carolina on primary day, but only Obama and Edwards arranged to speak to supporters after the polls closed. Clinton decided to fly to Tennessee, one of the Feb. 5 states, leaving as the polls were closing.
After playing a muted role in the earlier contests, the issue of race dominated an incendiary week that included a shift in strategy for Obama, a remarkably bitter debate and fresh scrutiny of the former president's role in his wife's campaign.
Each side accused the other of playing the race card, sparking a controversy that frequently involved Bill Clinton.
"They are getting votes, to be sure, because of their race or gender. That's why people tell me Hillary doesn't have a chance of winning here," former President Clinton said at one stop as he campaigned for his wife, strongly suggesting that blacks would not support a white alternative to Obama.
Clinton campaign strategists denied any intentional effort to stir the racial debate. But they said they believe the fallout has had the effect of branding Obama as "the black candidate," a tag that could hurt him outside the South.