For six of the seven Democratic hopefuls vying for the nomination to take on George Bush in November there is only one game in town: trying to stop the seventh - John Kerry.
Having been earlier written off as too distant and elitist, and overwhelmed by the surge of support for the former Vermont governor Howard Dean, Mr Kerry is now riding atop a steamroller in the run-up to Tuesday's seven crucial primaries. It is a fair bet that the contest to find a presidential candidate will be over by the end of the week.
With Mr Kerry having won convincing victories in Iowa and New Hampshire, polls released on Friday suggest he now leads the race in Arizona, Missouri and North Dakota. He is in a statistical tie for first place with Senator John Edwards in South Carolina, while he is running a competitive second to retired General Wesley Clark in Oklahoma. Mr Dean may be ahead in New Mexico, but his campaign is flagging and running out of funds, and while Senator Joe Lieberman is expected to win Delaware, the state has only a handful of delegates.
Mr Kerry's trick, it seems, is to present himself as the man with the best chance of beating Mr Bush in what will be a bitterly fought contest. "I saw some of the [Democratic candidates'] debate last night and I think John Kerry is the strongest candidate," said Claudia Philips, an insurance executive, as she made her way to work in Columbia, South Carolina's capital, on Friday morning. "I think it is because of his experience. I heard him speak in an earlier debate and he said you had to have experience in Washington if you are going to win."
Further proof of Mr Kerry's surge was provided by the very people he is seeking to challenge in November. Ken Mehlman, Mr Bush's campaign manager, accused the Massachusetts Senator and Vietnam veteran of being weak on national security.
"We value Senator Kerry's honourable and heroic service in Vietnam. But we question his judgement in consistently voting to cut defence and intelligence funding critical to national security," said Mr Mehlman, one of two senior Republicans to attack the Democratic front-runner.
"[In the mid-1980s] he sought to cancel the very weapons systems that are winning the war on terror and maintaining our military strength. He opposed Ronald Reagan's efforts to fight communism in our hemisphere and opposed the first Gulf War." The White House considers the experienced Mr Kerry a much tougher opponent than Mr Dean, and a poll in Newsweek suggested that in a head-to-head with the President, Mr Kerry could win by three points.
In an indication of the concern among administration officials, Mr Bush's campaign chief told party members: "We must expect an election where we will be behind at certain points, particularly after the Democrats settle on their nominee and hold their convention. This will not be easy. The country remains closely divided." Mr Kerry later said the Republicans were "scared stiff" of him.
"That is why they are sending their attack dogs out," he said. "I am going to fight back. It isn't going to work." Given the way these primaries have swerved and turned, however, Mr Kerry's victory is not certain. Mr Edwards is using South Carolina, the state in which he was born, to make a stand against Mr Kerry, pressing his case for the nomination by saying he can deliver the South to the Democrats - something that will have been noted by the party's strategists.
"Here is what I want you to tell your friends," the North Carolina Senator tells people in his energising stump speech. "The South is not George Bush's backyard. The South is my backyard. I want to beat George Bush in my backyard. I am ready for this fight. You have to give me a shot at George Bush. You give me a shot at George Bush and I will give you the White House."
History shows that no Democrat has secured the White House without winning at least some of the 11 Southern states. Al Gore would have been the exception in 2000, but for events in Florida and the intervention of the Supreme Court. Mr Kerry, meanwhile, has suggested that too much attention was paid to the South. "Gore proved that you can get elected President without winning one Southern state - if he had simply won New Hampshire," he said.
Such comments do not go down well among Southerners whose traditional antipathy to "northern liberals" appears as strong as ever. In historic Charleston, whose cobbled streets and antebellum houses make it probably America's most beautiful city, columnist Michael Graham wrote in the Charleston City Paper: "John Kerry will not get a 'good old boy' pass."
Mr Edwards will be hoping a victory here will push him beyond next Tuesday and give him the momentum to challenge in Michigan, Maine, Tennessee and Virginia, which all hold their primaries over the next 10 days. He may also be hoping that even if he cannot beat Mr Kerry, his strong showings and convincing campaign could see him placed on the ticket as vice-presidential running mate.
For many Democrats the Kerry/Edwards combination represents the North/South "dream-ticket" they believe could beat Mr Bush.
By Tom Carver
"Buy the latest Harry Potter and help send Joe Lieberman to the White House."
Did you know that you can contribute to the candidates in the presidential election on Amazon.com? So far, Clark, Dean and Edwards have raised about $7,000 (£3,865) a piece and Kerry, $15,000 - hardly enough for a TV ad in dusty Dubuque, but as a pointer to who might win the nomination, it's not bad.Incidentally, Brits and others frustrated at not being able to get a slice of the American election can buy shares in the candidates at www.intrade.com. Kerry's are currently doing better than Bush's, but since people from 122 countries have participated, it might not be the most reliable indicator.
John Kerry - Kennedy wannabe? Catholic, from Massachusetts, privately educated, name begins with K... Kerry has spent his entire political career in the shadow of the Kennedys. He worked for Ted's first Senate race back in 1962; now, 40 years on, Kennedy is the one stumping for Kerry. Their relationship has often been tricky. When Kerry expressed doubts about raising the minimum wage in 1995, Kennedy roared at him: "If you're not for [it], you don't deserve to call yourself a Democrat." On another occasion, they were travelling in the same car when Kennedy decided to exercise his dog, Splash. Since he was suffering from a bad back, he got Kerry to do it. "So that's my job now," he said later. "Throwing a tennis ball for Kennedy's dog."
Watching them on stage together in Iowa and New Hampshire, they seem to have developed a genuinely cordial relationship. Though whether a Kennedy at his side will help Kerry win the election is another matter. The Republicans are already planning to use the images to tar him as a "dangerous Massachusetts liberal".
I was beginning to nod off at the back of a Wes Clark rally in Keene, New Hampshire, when someone asked him about today's Super Bowl. It was a patsy of a question really, since Clark was wearing a jersey of the New England Patriots, the local team which happens to be in the final. But his answer was intriguing.
"When I lived in Colorado, I supported the Denver Broncos. When I lived in Washington, I supported the Redskins. Now I'm in New Hampshire, I support the Patriots." Can you trust a politician who changes his allegiances so easily? Hardly surprising, perhaps, that he's the only Democratic candidate who voted for Nixon and Reagan.
Tom Carver is Washington correspondent for BBC2's 'Newsnight'. You can contact him at email@example.comReuse content