Massachusetts Senator John Kerry on Monday night rode to victory in Iowa's kickoff presidential caucuses, upsetting front-runner Howard Dean and stunning caucus favourite Dick Gephardt.

Kerry's win sets the stage for a free-for-all in New Hampshire's follow-up primary.

"I want to thank Iowa for making me the Comeback Kerry," Kerry said in an interview with the Associated Press.

Just two weeks ago Dean and Gephardt were considered the favourites. The defeat of Gephardt, winner of the 1988 caucuses, puts a question mark on his political career.

"We came from behind here, and we came for a fight here, and my message is now to the special interest who call the White House home: We're coming to you," Kerry said.

With 98 per cent of the precincts reporting, Kerry had 38 per cent, Edwards 32 per cent, Dean 18 per cent and Gephardt 11 per cent.

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Caucuses are a series of precinct meetings across the state, held mostly in public buildings but also in churches and community centres, where local party members choose delegates for the party's national convention this summer.

The delegates in turn choose the party's presidential nominee.

Iowa has 45 delegates out of 2,162 needed to claim the nomination. A total of eight Democrats are vying for their party's endorsement to run against Bush.

The surprise, however, was the strong showing of North Carolina Senator John Edwards, who a few weeks ago, was polling in single digits in Iowa.

"It feels terrific. What's happened here the last two weeks with my campaign has been phenomenal," Edwards told USA Today. "We're very excited about what's happening tonight."

Edwards was elected to the Senate from North Carolina in 1998, after building a career as a successful trial attorney. He has said his southern roots would be important in mounting a successful challenge to President Bush.

Former Vermont governor Howard Dean admitted defeat, but pledged to fight on in New Hampshire.

"I can't tell where we're going to finish yet, but the early numbers look like Senator Kerry will win it and I certainly want to congratulate him and Senator (John) Edwards for a great campaign," Dean said in an interview on CNN's 'Larry King Live' when it became clear that Kerry would emerge victorious.

"Certainly we'd like to have done better, but we worked hard, we've got a lot of great people working for us, and on to New Hampshire," Dean added. New Hampshire holds its first-in-the-nation presidential primary on January 27.

Agencies