By Kevin Anderson
BBC News Online in Washington
Senator John Edwards has sharpened his attacks on Democrat front-runner John Kerry as a key round of 10 presidential primary contests looms in the US.
The two front-runners face a key test on Super Tuesday
Mr Edwards knows that he must win some states on "Super Tuesday" this week if he is to slow Mr Kerry's momentum.
In a TV debate he attacked Mr Kerry's record on trade and tried to portray his rival as a Washington insider out of touch with average Americans.
But without wins on Tuesday, pressure will mount on him to exit the race.
Mr Edwards trails in the polls, but he said he would stay in the race whatever the results on Tuesday.
Since a fiery early debate ahead of the caucuses in Iowa, the candidates have taken great pains to be civil.
But as Katharine Seelye of the New York Times wrote in a snap analysis of Sunday's debate: "It is clear that the candidates know how high the stakes are, with increasingly sharp attacks against each other.
KEY CAMPAIGN DATES
2 March - 'Super Tuesday' primaries held in 10 states, including California, Georgia, New York, Ohio
9 March - Primaries in Florida, Louisiana, Mississippi, Texas
26-29 July - Democrat national convention in Boston
30 Aug-2 Sep - Republican national convention in New York
2 Nov - Presidential election
"Kerry and Edwards know that Kerry needs to keep Edwards from gaining any kind of foothold on Tuesday that could keep his campaign going," she said.
Mr Edwards aggressively attacked the front-runner on budget-busting policy proposals and on his trade record.
He pointed to Mr Kerry's support for trade agreements with Chile, Singapore, Africa and the Caribbean, as well as for broader trade negotiation powers for the president.
Mr Kerry countered that he had fought for worker and environmental protections in the agreements.
It was an exchange that the two leading candidates have had in previous debates, but this time, Mr Edwards pushed harder, criticising Mr Kerry's trade solutions as "the same old Washington talk".
"The fundamental issue in this election is whether the people of this country believe that we're going to get change that originates in Washington or change that has to come from out there in the real world," Mr Edwards said.
But yet again, the candidates spent as much if not more time attacking President George Bush than attacking each other, although Al Sharpton and Dennis Kucinich fought to be heard.
The debate was the last opportunity for all four remaining candidates
They all attacked President Bush for neglecting the situation in Haiti until it became a crisis.
"He's late, as usual," Mr Kerry said of the president. "I never would have allowed it to get out of control the way it did."
And Mr Edwards criticised President Bush's calls for a policy of pre-emption, when he said what the US really needed was a policy of prevention.
The candidates again faced questions on gay marriage after President Bush called for passage of an amendment to the US constitution that would define marriage as exclusively between a man and a woman.
Both Mr Kerry and Mr Edwards reiterated their opposition to same-sex marriage but their support for equal rights for same-sex couples under civil unions.
The race ahead
John Kerry has won 18 of 20 contests this far. John Edwards has had one victory - in his native state of South Carolina.
But Mr Edwards, with his easy charm and working-class roots, is seen as the best alternative to Mr Kerry.
According to Ms Seelye, during the debate on US policy towards North Korea, Mr Kerry had a chance to "show his breadth of understanding and historical perspective".
But "Edwards seems better able to articulate these problems in accessible language," she added.
The senator from North Carolina hopes to win several races on Super Tuesday to keep his candidacy alive through 9 March, with contests in four southern states.
Many in the party believe the Democratic dream team would be a Kerry-Edwards ticket, with Mr Edwards running as vice-president.
But Mr Edwards is not ready to call it quits, and he dismissed that suggestion during the debate, saying "Oh, no! Far from it".