GREENVILLE, S.C. - Fresh from their first debate, Democratic presidential candidates prodded their rivals on war and health care yesterday, seeking an advantage with voters in the South's first primary state.

Sen. Hillary Rodham Clinton of New York stressed her military-tough answer in Thursday's debate as she sought to draw a distinction with her top foe, Sen. Barack Obama of Illinois. John Edwards of North Carolina challenged his former Senate colleagues to stand up to President Bush on the Iraq war.

The stakes were clear to all eight Democrats vying for the nomination.

South Carolina holds its Democratic primary Jan. 29, and the winner will have momentum heading into the Feb. 5 megaprimary, when multiple states - including New Jersey, California and New York - cast ballots.

Edwards, the 2004 vice presidential nominee, leads in polls in the first caucus state, Iowa, and Clinton is ahead in the first primary state in the nation, New Hampshire. Absent recent reliable polling in South Carolina, the candidates spent the day campaigning to build support in the state.

Obama, who held a town-hall meeting in Charleston, has natural appeal in South Carolina, where nearly 50 percent of the Democratic primary voters are black.

Clinton was not about to cede him that bloc. She stopped at the home of octogenarian Helen Jackson, the mother of civil rights activist Jesse Jackson, and invited a photographer for the local newspaper. The younger Jackson is backing Obama.

Throughout her campaign swing, which included a stop at a charter school, Clinton mentioned her husband, former President Bill Clinton, whom black voters widely embraced during his time in office.

Hillary Clinton, in an effort to burnish her national security credentials, also reminded voters about her debate answer on how she would respond to a terrorist attack by al-Qaeda. She said she would retaliate. Obama, facing a similar question, did not mention retaliation.

"I said that as president, any president, would have to respond as swiftly as is prudent," she said during a town-hall meeting in Greenville, one of South Carolina's conservative strongholds. "We would retaliate because the United States must defend our interests, our people and our country."

In Charleston, Edwards called on his rivals to stand up to Bush when, as expected, he vetoes legislation next week that would mandate withdrawal of U.S. forces from Iraq.

"We had a bunch of members of the United States Congress on stage" Edwards said of his former Senate colleagues. "What are they going to do? They should not back down from this president, because this is not about politics. It's about life and death and war."

Without mentioning names, Edwards also took a swipe at Obama, who tried to explain his health-care plan within the 60-second limit for answers.

"It's not enough to say we need universal health care and two or three broad generalities," Edwards said. "That's not a specific health-care plan."

See what caught columnist Dick Polman's eye in the Democrats' first debate,

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