John Edwards, who was John Kerry's Presidential running mate two years ago, today became the first heavyweight Democrat to declare his intention to run for the White House in 2008.

More than two years before President George Bush leaves office, there are now three Democratic contenders officially in the race to replace him.

Making his announcement this morning, Mr Edwards joined two outsiders — Tom Vilsack, the Governor of Iowa, and Congressman Dennis Kucinich, of Ohio — already on the campaign trail.

Senators Hillary Clinton of New York and Barack Obama, of Illinois, and Governor Mitt Romney, of Massachusetts, are expected to follow his example in the coming weeks.

Mr Edwards, a former personal injury lawyer from North Carolina, was a surprise star of the 2004 campaign for the Democratic nomination, winning the South Carolina primary and finishing second to Senator John Kerry. Handsome and a vigorous debater he was rewarded with the Democratic nomination for the Vice Presidency.

He is widely regarded to have been planning his second run for the White House ever since President Bush won his second term. In the last two years, Mr Edwards has sought to strengthen his relations with labour unions and improve his foreign policy credentials, which were perceived as a weakness in 2004.

Seeking to take advantage of the slow news days after Christmas Mr Edwards launched his campaign in the backyard of a house damaged by Hurricane Katrina in New Orleans last year.

Wearing jeans and an open-necked shirt, Mr Edwards, 53, worked with local youngsters to repair the house, his labour interspersed with interviews on America's breakfast news programmes.

"I’m here in New Orleans... to announce that I’m a candidate for the presidency of the United States in the election in 2008," he said. "To show what’s possible when we as Americans, instead of staying home and complaining about somebody else not doing what they’re supposed to, we actually take responsibility and we take action."

"That’s what’s going to be the basis for my campaign. This campaign will be a grassroots, ground-up campaign, where we ask people to take action.

"It’s not like we don’t know what needs to be done, and this is not rocket science."

In an early version of the stump speech he will hope to repeat hundreds of times in the coming 22 months, Mr Edwards described an agenda that included leading the fight against global warming, curbing America's consumption of oil, combating poverty and "providing moral leadership in the world, starting with Iraq".

America's presidential campaigns are becoming longer and longer as lower-profile candidates declare their nominations early, seeking to grab a few headlines and recruit staff before the major, well-financed players join and dominate the field. While short of the star power of Mrs Clinton and Mr Obama, Mr Edwards is seen as a savvy contender whose roots in the Carolinas may help the Democrats win back the South.

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