Former Nader's raiders are determined to stop the man they believe lost the 2000 election for the Democrats doing so once again. He says that if the US constitution means anything, it is his right to put his name on the ballot paper

Four years on, the US presidential election is again a dead heat betweense a radical conservative and a mainstream liberal. And once more, Ralph Nader's oddball candidacy threatens to tip the delicate balance to the right.

This time the consumer activist is a much reduced force. The overwhelming majority of his closest aides and supporters have defected, including Michael Moore. The film-maker went down on his knees on cable television to beg Mr Nader to withdraw. Even his former running mate, Winona LaDuke, has come out for John Kerry.

Four years ago, Mr Nader was the Green party candidate, backed by its modest but enthusiastic machine.

This time, he is on his own. All he has is patchy backing, in some states, of the Reform party, a conservative, libertarian group a long, long way from his progressive roots.

Mr Nader took 2.7% in 2000. In recent weeks, his rating has been closer to 1%. But that support is up to 4%, in some of the swing states. In any case, 1% can easily be the difference between victory and defeat for President George Bush and Senator Kerry.

In 2000 Mr Nader took almost 100,000 votes in Florida. Al Gore lost (after supreme court intervention) by 537 votes. That is why the Democratic party, abetted by many former "Nader's Raiders", shock troops of the civic activism Mr Nader pioneered, have spent six months desperately trying to keep him off the ballot papers.

Like all civil wars, it has been nasty. "It's beyond bitter," said Toby Moffett, formerly one of Mr Nader's oldest friends and now leader of the legal campaign to stop him. "He likes to say whoever used to be in his movement and is now against him is corrupt and a sellout. We think he has totally lost his bearings."

The Nader campaign has been helped by rightwingers well aware of its potential to split the progressive vote. Naderites have also resorted to dubious means to obtain signatures on state petitions to get his name on the ballot. Homeless people were paid for every signature they collected; thousands were found to have been forged in the battleground states of Ohio and Pennsylvania, scrawled alongside names and addresses copied out of a phone directory.

Anti-Nader forces, meanwhile, have fought a legal war of attrition, bringing one case after another with the intention of driving him out of the race.

They have not succeeded. The 70-year-old is an independent in every sense. Political isolation only deepens his martyr's sense of righteousness. "I always thought that running for elective office is the consummate expression of the right to free speech, assembly, and petition under our first amendment. It shouldn't be that difficult in a democracy to get on the ballot," he told University of Minnesota students.

He has fought his way on to the ballot in nearly 40 states. But legal objections to the dodgy signatures in Ohio and Pennsylvania have kept him out of two of the tightest and biggest battlegrounds, and the legal struggle has drained his resources. The anti-Nader campaign, combined with Senator Kerry's powerful performance in the debates and outspoken opposition to the Iraq war, have helped erode Mr Nader's backing in the polls from 5% in the spring to the current 1% rump.

Anna Greenberg, a pollster with Democratic party ties, said the Nader vote was now very different from four years ago. Its profile now more closely resembles the voters who backed Ross Perot, a maverick conservative Texan who ran in 1992 and 1996.

"In 2000 you had younger collegeeducated males who were progressive and interested in environmentalist issues," she said. "This time it's more like the Perot vote in the 90s: economically populist, anti-corporate, blue collar. They are much more conservative than Nader 2000."

According to recent Gallup figures, when Nader supporters were asked who they would vote for if he were not on the ballot, 52 % opted for Mr Bush. Ms Greenberg disagrees. Her polling tells her Mr Nader still hurts Mr Kerry more than Mr Bush, although by a much smaller degree than a few months ago.

In swing states where Mr Nader has slightly more backing, Iowa, Wisconsin, New Hampshire, New Mexico and Florida, most pollsters believe he still poses a greater threat to the Democrat. The Democrats certainly think so. More than 75 former Nader's Raiders published an open letter: "As the recipient of financial and political support from rightwing campaign donors, Ralph is party to a disingenuous effort to split the progressive vote in key states. With the major party candidates in a dead heat, Nader is poised to tip the election to Bush - again."

The ex-raiders will be using phones and chatrooms to convince likeminded Americans to switch their votes.

Yet Mr Nader soldiers on, yesterday kicking off a tour of a dozen states with a trip to Florida. His sheer determination is a testament to his single-mindedness. He has never married, and has few interests other than political reform.

It was bred in the bone. His father, Nathra, a Lebanese immigrant, ran a restaurant in Winsted, Connecticut, where his forthright political views were served up along with the food.

Around the dinner table, the young Ralph was called on to explain and defend his beliefs. "I spent countless nights around that table eating wonderful Arabic food, and talking to his father and mother," Mr Moffett, a fellow Lebanese-American recalls. "They were very principled people, very idealistic people, but they were also out there. They were not interested in marginal victories, only the absolute will do."

The young Ralph hated working in a small Connecticut law firm. Restless, he spent his summers hitchhiking across the country talking to truckers and travelling salesmen. What struck him was how dangerous their work was. Their vehicles were death-traps. Getting a job as a congressional aide in the early 1960s, he researched the car industry and in 1965, produced Unsafe at Any Speed, an indictment of modern cars, particularly the Chevrolet Corsair.

For years it was Ralph Nader against General Motors, who went so far as to hire private detectives to discredit him. They sent a prostitute to try to seduce him at a food counter at Safeway's but he turned her away. So the gumshoes tried to prove he was homosexual but were caught as they tried to follow him into Congress. The scandal made Mr Nader into a hero overnight. The car makers were forced to introduce seat belts, and ultimately air bags.

In the 1970s, Mr Nader toured the country again, this time urging students to set up public interest research groups for consumer and environmental reform. Ken Ward was a Massachusetts student in 1976. "He was talking to people afterwards, and there was a professor talking about this method of turning cow manure into methane, and using it for energy," Mr Ward said. "And we got into a car and drove out in the middle of nowhere to go look at cow manure, at 1.30 in the morning. Most college speakers and politicians don't do that." Mr Ward became a follower and has spent his career as a consumer activist. Like so many other Raiders, he has joined the stop-Ralph effort.

"In his own mind, he thinks the risk of four more years of George W Bush is worth it to him. But how does that work, if by every single indicator it's done nothing?"

Some critics put his perseverance down to sheer ego. But an egoist would be unnerved by the rising chorus of denigration. Mr Nader's certainty is so strong that defeat only reinforces it.

"We lose to win, eventually," he told the New York Times. "That's the story of social justice. You have to be willing to lose and fight, and lose and fight, and lose and fight. Until the agenda is won."

However, former supporters see only a stubborn old man running on pride.

"It's the whole St Ralph syndrome. He's pure, and we're all corrupt.

"He's just out there somewhere where it can't be reached," Mr Moffett said. "He's afraid something might be won in a marginal way. He's only for overwhelming victory."



Born

February 27 1934, in Winsted, Connecticut, to Lebanese immigrants, Nathra and Rose Nader

Education

Graduated from Princeton in 1955 and Harvard law school in 1958. In 1963 he hitchhiked to Washington and got a job working for then assistant secretary of labour Daniel Moynihan

· In 1965 he released a study claiming that American cars were structurally flawed. General Motors hired private detectives to try to discredit him, but Nader successfully sued for invasion of privacy and used the money to become a champion of consumer rights

· In 1971 he founded the Public Citizen non-profit organisation, credited with helping to pass the Safe Drinking Water Act and Freedom of Information Act

· He was the Greens' presidential candidate in 1996 and 2000. This year he is running as an independent