Bill Clinton stands on a small stage in this tiny town, torrential rain beating on the rooftop, his all-white crowd of coalminers, schoolteachers and union members cheering him on. “Don’t let them tell you she can’t win this thing,” he hollers, his voice hoarse after another day of campaigning. “I’m telling you, she can win this thing, because of people like you, and places like this.”

There is huge affection for Mr Clinton in West Virginia, where his wife faces her next primary contest with Barack Obama on Tuesday. The former First Lady holds an overwhelming 25-point lead among one of the whitest, oldest and most rural electorates in America. The state voted for her husband twice, but backed President Bush in the last two elections.

Yet as the former President appears before loyal crowds across small town Appalachia, and his wife stubbornly refuses to heed calls for her to quit the race, there is a palpable sense for many Democrats that they are witnessing a changing of the guard, the final days of the House of Clinton, after 16 years of dominance.

Even as Mr Clinton spoke, Mr Obama was paying a surprise visit to the House of Representatives, where congressman flocked around him, grasping for the hand of the man many believe is about to become their new leader. Five more super-delegates pledged their support for Mr Obama yesterday, including one who had previously backed Mrs Clinton.

But if Mr Obama has his sights on a general election against John McCain, he has a more immediate and equally testing challenge: how to unite a party, and a Democratic electorate, where large, crucial swaths of voters – especially white, blue-collar and the elderly – remain passionately loyal to the Clintons, and openly hostile to him.

As Mr Clinton’s barnstorming performance in Fairlea proved, he is still a potent force, and Mr Obama is going to need him, his wife and their supporters on side if he harbours any hope of reaching the White House.

It will not be easy. Such is the hostility among many of their supporters, that nearly half of Mrs Clinton’s backers in Indiana said they would not vote for Mr Obama if he were nominated. More than a third in Pennsylvania said the same. Not one Clinton supporter met by The Times in West Virginia said they would turn out for the Illinois senator. “You’d have to twist my arm a long way,” said Lonnie Ward, 62, a retired miner queueing to see Mr Clinton next to Cowboy Dan’s Meathouse. “Bill’s my main man.” Peggy Bland, 69, said: “She’s a strong, strong, strong lady.” And Mr Obama? “Oh no, I wouldn’t vote for him.”

Matthew Towsley, who has been selling Hillary and Obama badges, said: “It’s got real bad. Unless they can put them on the same ticket, there’s going to be trouble.”

Mr Obama’s big win in North Carolina last week, and Mrs Clinton’s narrow victory in Indiana, means the nomination is within his grasp. He is planning to declare a victory of sorts on May 20, after the contests in Kentucky and Oregon, when he expects to have secured a majority among the pledged delegates on offer.

Yet Mrs Clinton and her husband passionately believe that she is a better candidate to take on Mr McCain. She correctly pointed out on Thursday that she has a much broader base of support, even plunging into the minefield of racial politics by declaring that Mr Obama’s backing among “white Americans” was weakening.

In recent contests, she has won Ohio, Pennsylvania and Indiana with overwhelming backing from whites, blue-collar voters, women, and voters over 45. Mr Obama has been propelled toward the nomination mostly by African-Americans, the young, and the well educated. Paul Begala, a former Clinton strategist, inartfully summed up their case: “We can’t win just with African-Americans and egg-heads.”

Howard Dean, the Democratic party chairman, whose once-promising 2004 presidential bid collapsed in Iowa, said he spent months trying to persuade his supporters to rally behind John Kerry, the nominee. And they did not even dislike Mr Kerry. Gary Hart said that after he lost his divisive primary battle against Walter Mondale in 1984, he worked tirelessly – and held more than 40 campaign events – imploring his supporters to back the nominee. “And I was not able to move [them],” he said.

Even if Mrs Clinton loses, she will return to the Senate one of the most powerful politicians in the US. Yet for now, she has tens of millions of supporters across America that believe the House of Clinton must not fall.

Tit for tat

— Hillary Clinton may have to rely on sales of merchandise to revive her finances; $21.95 will buy a Hillary nutcracker

— In the 2004 race John Kerry, the Democrat challenger to President Bush, was accused of “flip-flopping” on issues, hence John Kerry flip-flop sandals

— One of the 2004 slogans, “Save a tree. Remove a Bush”, appeared on merchandise

— A Barack Obama thong is on sale at $9

— Election Protection Condoms for $11.95 a dozen, feature “the likeness of some of our most influential Americans”

Times research

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