WASHINGTON, US - Former senator John Edwards Wednesday dropped out of the Democratic White House race transforming it into a straight fight between bitter rivals Hillary Clinton and Barack Obama.

"It's time for me to step aside so that history ... can blaze its path," he told a rally in New Orleans, adding that despite the bitter campaign the Democratic Party would rally around the eventual nominee to take back the White House in the November presidential elections.

"Today I am suspending my campaign for the Democratic nomination for the presidency," he added.

Edwards's decision to abandon his second quest for the presidency after a slew of poor performances, leaves the field clear for Clinton and Obama to battle it out for the party's nomination.

He said both of the leading Democratic hopefuls had pledged to him that they would take up his cause of championing the poor middle-classes and ending poverty in the United States. But he did not endorse any of his rivals.

Despite coming a respectable second to Obama in the very first vote in Iowa early this month, Edwards, 54, whose wife Elizabeth has incurable cancer, has failed to shine since, limping in third in all the other primaries so far.

He even admitted to getting his "butt kicked" in Nevada, where Clinton, 60, triumphed adding to her victories in New Hampshire and Michigan.

A hefty defeat in Florida late Tuesday proved to be the final blow for the former senator who also lost his 2004 tilt at the White House. Clinton coasted to a symbolic victory in Florida with 50 percent, which boosts her bid to be America's first woman president ahead of next week?s SuperTuesday when some 22 states will vote for their candidates.

Veteran Democratic strategist Donna Brazile said both remaining candidates could benefit from Edwards's withdrawal: Obama might pick up those backers eager for change to add to his wins in Iowa and South Carolina, while Clinton could grab some of his hefty labor support.

"But long term, the candidate who talks about the plight of the poor, that champions the middle class, that talks about trade and health care ... will benefit from the support of John Edwards," Brazile told CNN. Clinton, 60, and Obama, 46, who have fought a bitter battle for voters, will again square off in a Democratic debate scheduled for Thursday in California.

Obama paid tribute to Edwards saying he "has spent a lifetime fighting to give voice to the voiceless and hope to the struggling, even when it wasn?t popular to do or covered in the news."

"At a time when our politics is too focused on who's up and who's down, he made a nation focus again on who matters."

Clinton also praised Edwards saying he had ?ended his campaign today in the same way he started it - by standing with the people who are too often left behind and nearly always left out of our national debate."

"John ran with compassion and conviction and lifted this campaign with his deep concern for the daily lives of the American people," she said in a statement, adding "John is one of the greatest champions the American people could ask for."

The most expensive and most protracted White House race in history was also set to claim another victim with Giuliani widely expected to bow out and endorse McCain helping to narrow down the muddied Republican field.

Arizona Senator McCain, who was once given up for lost after almost running out of money in mid-2006, was celebrating after his win in Florida late Tuesday pushed him to the front of the Republican pack.

McCain, 71, beat former Massachusetts governor Mitt Romney to take 36 percent of the vote and over 29 percent for Romney. Giuliani came in third with 15 percent, and ordained Baptist preacher Mike Huckabee won 13 percent.

"My friends, in one week, in one week we will have as close to a national primary as we've ever had in this country. I intend to win it and be the nominee of our party!" McCain told supporters late Tuesday.

McCain and Romney were due to face off late Wednesday in a CNN Republican debate in Los Angeles. --AFP