Atlanta ? John Edwards, whose Southern charm and oratorical flair transformed the Democratic presidential contest, finally gave in to the inevitable math of the primary contest on Tuesday, bowing out with the same unbridled optimism that has characterized his candidacy.

“We have been the little engine that could,” the North Carolina senator told supporters as he signaled he was abandoning his challenge to front-runner John Kerry. He planned to formally announce he is dropping out of the race today in Raleigh, N.C.

Edwards won his native South Carolina and managed to come from the backfield in a once-crowded Democratic race with a string of strong second-place finishes to be the last major challenger to Kerry.

Edwards congratulated Kerry in a speech to supporters, signaling that Democrats would present a united front against Bush in the fall.

He called his Senate colleague from Massachusetts an “extraordinary advocate for jobs, better health care, a safer world.”

“These are the causes of our party, these are the causes of our country, and these are the causes we will prevail on come November,” Edwards said.

He credited Kerry with running “a strong, powerful campaign.”

Uniting with Kerry

In a telephone call to Kerry, Edwards implied that he would drop out and told Kerry he wanted to sit down and talk with him about unifying the party, said Kerry spokesman David Wade. The two also talked about how they “rode out the tough times” and the contributions and sacrifices that their wives had made throughout the campaign, Wade said.

Democratic presidential hopeful Sen. John Edwards, D-N.C., points to supporters during a primary-night rally. Edwards congratulated Sen. John Kerry in a speech Tuesday night, and he is expected to drop out of the race today.

Kerry, in turn, credited Edwards for bringing “a compelling voice to our party, great eloquence … and great promise for leadership for the years to come.”

Edwards appealed to independents and other potential swing voters who could be instrumental in a close contest in the fall. Although he made millions as a plaintiff’s trial lawyer before running for the Senate for the first time in 1998, Edwards emphasized his humble origins as the son of a textile mill worker who had lost his job when his factory closed.