As the Democratic ticket conceded the presidential race at Fanueil Hall, Sen. John Edwards (D-N.C.) pledged that "the battle for you, the hardworking Americans who built this country, rages on."

What role Edwards might play in that battle became a wide-open question on Wednesday. John F. Kerry's loss to President Bush brought an abrupt end -- at least for now -- to his running mate's remarkably rapid rise in national politics.

Come January, Edwards will retire from the Senate after a single term, having decided last summer to forgo a 2004 reelection bid so that he might focus on his campaign for the Democratic presidential nomination.

Democratic officials expect Edwards, who received mixed reviews in the No. 2 slot, to make another run for the White House in 2008. But so might several other Democrats, including one of the party's luminaries, Sen. Hillary Rodham Clinton of New York. Moreover, it is unclear how well Edwards, a former trial lawyer, might maintain his visibility in the meantime.

Ed Turlington, a Raleigh, N.C., lawyer who served as general chairman of Edwards's campaign for the Democratic nomination, said he expects Edwards to remain in high demand as a speaker at party functions and as an important voice for Democrats nationally. Turlington suggested it is too early to talk about the 2008 race, but he did not exactly tamp down expectations.

"History has shown us there are varying paths to the White House," Turlington said, citing the presidencies of Richard M. Nixon, Jimmy Carter and Ronald Reagan, all of whom were elected when they were not in political office.

If Edwards pursues the presidency again, he will almost certainly face flak for Tuesday's results in his home state: Bush prevailed over Kerry by 13 percentage points, the same margin by which Bush beat Al Gore in North Carolina in 2000. Although the state has trended Republican in presidential elections since 1980, Edwards's presence on the ticket had been forecast to make the race more competitive this year.

More broadly, Kerry's selection of Edwards in July was greeted with mostly favorable reviews, and most analysts thought he held his own in his debate with Vice President Cheney. Edwards faced some criticism for not being visible enough on the campaign early on.

Michael Munger, a political science professor at Duke University, said that was a case of Kerry's campaign failing to properly showcase Edwards's talent and rhetoric about "two Americas" from the primaries.

"Edwards was a thoroughbred, and they kept him in the barn," Munger said. "I think he's far from dead."

Although Edwards dutifully played the No. 2 role on the ticket, there were also periodic reminders in recent weeks of his ambitions.

Appearing two Sundays before the election at Allen Temple African Methodist Episcopal Church in Cincinnati, he was introduced this way by the Rev. Donald H. Jordan Sr.: "John Edwards is going to be the president of the United States. I don't know when. I don't know how. But mark my words: This man is going to be the president of the United States."

Sen. John Edwards gives Teresa Heinz Kerry a hug after concession speech by Sen. John F. Kerry in Boston.