In wooing a faithful Democratic constituency, Obama faces two-term New York Sen. Hillary Rodham Clinton, the party front-runner who enjoys strong support in the black community. She also is married to former President Clinton, so wildly popular among black voters that novelist Toni Morrison dubbed him "the first black president" in a 1998 essay.

Obama also must contend with John Edwards, the 2004 vice presidential nominee who has won praise from black leaders for his commitment to fighting poverty. It was Edwards who recently addressed a high-profile New York commemoration of Martin Luther King Jr. — at the invitation of the slain civil rights leader's son.

"It will be a challenge because (Obama) will be competing against people who have relationships in the black community," said the Rev. Jesse Jackson, who ran for the Democratic presidential nomination twice in the 1980s.

Jackson, who won 13 primaries and caucuses in 1988, said he is leaning toward supporting Obama's candidacy but hasn't made an endorsement. His son, Rep. Jesse Jackson Jr. of Illinois, is backing Obama.

For all his promise, Obama is a relatively new face on the national political scene and remains unknown to many voters, including blacks.

An Associated Press-Ipsos poll last October found Sen. Clinton with the support of 25 percent of black voters compared with 10 percent for Obama. Former President Clinton, who is barred by term limits from running again, garnered 5 percent.

Black voters will be crucial in some of the early party primaries such as South Carolina on Jan. 29 and Alabama on Feb. 5. In 2004, blacks made up nearly 50 percent of the Democratic primary vote in South Carolina; in Alabama, it was closer to 55 percent.

Obama also may not be the only black candidate in the field. Civil rights activist Al Sharpton, who ran for president in 2004, says he is considering another bid, in part out of his frustration that no candidate is directly addressing urban issues.

Sharpton was in Washington on Thursday to meet with several candidates, including Clinton, Obama, Connecticut Sen. Chris Dodd and Delaware Sen. Joe Biden, to question them on their views before deciding whether to enter the field.

David Bositis of the Joint Center for Political Studies said Obama needs to avoid the candidate mold of a Jackson or Sharpton, whose appeal did not extended much beyond a core black audience.

"A black candidate who's mainly advocating for civil rights these days is not going to go anywhere in a presidential election," Bositis said. "I think he (Obama) will get substantial support from blacks, but not all blacks. Some black voters are going to find him — what? Too white."

Obama was asked recently whether he might be "too white" to appeal to black voters.

"If you look at my black vote in my U.S. Senate race or my approval ratings back in Illinois, I feel pretty confident that once folks know who I am, then we will do just fine," he said.

Obama, 45, does not fit the familiar mode of King's generation of black leaders. He is biracial — his white mother was from Kansas, his father Kenyan — and was educated at Ivy League universities.

In his first of two best-selling memoirs, "Dreams From My Father," Obama said he couldn't even get in the door at national civil rights groups when he was younger. He wrote letters to them after graduating from Columbia University but said none responded.

And while many voters have warmed to Obama's themes of political reconciliation and national unity, analysts say the message may not resonate as clearly with black voters.

"Barack Obama might not be considered a black candidate for traditional black voters, given their history," said Ronald Walters, director of the African-American Leadership Institute at the University of Maryland. "Obama has talked about America wanting a new kind of leadership. What is he talking about? He hasn't defined that sufficiently."

Still, some civil rights leaders already are claiming him as a major step forward for black American leadership — even if he didn't spring from their movement.

"Many are anxious to separate Barack Obama's campaign from the civil rights struggle, but that is not true," said the elder Jackson. "It's an extension of our struggle. His running — you could draw a straight line from his campaign to our (voting rights) marches in Selma in 1965."

Yet Obama's background also makes him appealing to whites, said Carol M. Swain, a law professor at Vanderbilt University. "He's a black candidate, but he's not into invoking white guilt," she said. "He comes across as a consensus builder."

There have been just a handful of black presidential candidates. Among them: Sharpton and former Illinois Sen. Carol Moseley Braun in 2004; Republican Alan Keyes in 1996 and 2000; and Democratic Rep. Shirley Chisholm in 1972.