John Edwards (search) suggested Wednesday that presidential rivals Howard Dean and John Kerry would be a drag at the top of the ticket in key southern congressional races, and said he could help "everywhere in the country."

"I know I can strengthen our position because I've won in a tough place, a really tough place," said Edwards, who won his North Carolina Senate seat in 1998 by defeating a Republican incumbent.

Edwards made his remarks as he campaigned in two states -- South Carolina and New Hampshire -- with distinctly different electorates and political challenges.

He has long looked to South Carolina, which holds a primary Feb. 3, for his first victory in the nominating campaign and has reached out to Rep. Jim Clyburn (search), the state's only black congressman. Clyburn is being courted again by all the candidates after the one he endorsed, Rep. Dick Gephardt, withdrew from the race this week.

At the same time, a startlingly strong second-place finish in the Iowa caucuses gives him hope of springing yet another surprise on Tuesday in New Hampshire. The state holds the first-in-the-nation primary next door to Dean's Vermont and Kerry's Massachusetts.

Edwards, who speaks in southern cadences, told an audience in Greenville, S.C., that he is the candidate who can beat President Bush in every region of the country. He drew applause when he said the key to victory was "talking like this, in the south."

The North Carolinian generally makes similar claims at every appearance as he, like his rivals, tries to woo Democrats in a theme of "electability" against Bush.

Hours later, at a small New England diner, he broadened that appeal when one voter asked how he could fulfill his legislative agenda with a GOP-controlled Congress.

Edwards responded by stressing the importance of increasing Democratic strength in Congress. He added that the key to that is prevailing in swing seats such as the one that conservative Democratic Sen. Zell Miller (search) of Georgia will leave when he retires at the end of the year.

"The question is who on the top of the Democratic ticket can go every place in America and campaign with the candidates and strengthen their ability to get elected. And who will make it more difficult for them to get elected?" Edwards said.

"So if you're a Democrat running in a tight race ... in Georgia, do you want John Edwards campaigning with you? Do you want Howard Dean campaigning with you? Do you want John Kerry campaigning with you?

"I mean it gets to be a fairly basic question ... and I will let you make your own judgment."

Kerry, asked about Edwards' remarks in a television interview, dismissed them.

"Well Max Cleland (search) is on my side and I think will testify" that he can win in the South. "I look forward to campaigning in Georgia or in South Carolina and I think the team that I have down south there is terrific," he said.

Cleland is a triple amputee as a result of Vietnam War injuries. He served one term in the Senate before losing his seat to a Republican in 2002.

Clyburn, meanwhile, said he is uncertain about which of the remaining candidates to support. An endorsement by the six-term congressman could help galvanize support among blacks, who could make up much of the state's primary electorate.

Clyburn said he would consult family and friends about another possible endorsement, but does not expect to make a decision until after the New Hampshire primary.

Edwards' remarks amounted to a glancing blow against his rivals, and he did not mention retired Gen. Wesley Clark (search), an Arkansas native who -- like Kerry and Dean -- runs ahead of him in New Hampshire polling.

Still, by mentioning his two New England-based competitors by name, Edwards injected a new element into the electability debate-- expanding it beyond the race for the White House to include Congress.

Edwards did not say so, but Democrats are particularly vulnerable to the loss of Senate seats across the South this year as they struggle to close a GOP majority of 51-48, with one Democrat-leaning independent.

He has announced his own retirement from the Senate, and in addition to Miller, southern Democrats are stepping down in South Carolina, Florida and Louisiana. Those five seats give Republicans a string of opportunities for gains across a region where Bush is expected to run particularly well in November.

Political strategists in both parties also have identified a number of southern House seats that figure to be competitive next year.