Democrats are moving on decisively from their long debate about whether Barack Obama will be their presidential nominee. Instead, the party is now asking when Hillary Clinton will admit defeat and — more importantly — how she might quit the race.

Mrs Clinton, for the moment, remains defiant and indefatigable. She campaigned across three time zones in West Virginia, South Dakota and Oregon yesterday, pressing her case that she remains the strongest general election candidate against John McCain, the Republican.

In a newspaper interview she unashamedly pointed out that Mr Obama, on the brink of becoming the first black American presidential nominee, has failed to win over the white vote.

“I have a much broader base to build a winning coalition on,” she said, citing exit polls from the primaries this week that show “Senator Obama’s support among working, hard-working Americans, white Americans, is weakening again — there’s a pattern emerging here”.

Mrs Clinton has refrained from repeating the attacks on Mr Obama’s policies, character and judgment that featured prominently in her campaign over the past two months.

In their place are frequent notes of grace and repeated promises that she will help to unite the party when the race is over.

Much of the Democratic party leadership is thought to be content for the contest to continue, perhaps all the way to the final primaries on June 3, on condition that it is not scarred by negative attacks that would damage their party’s prospects of retaking the White House in November.

Senator Dianne Feinstein, one of the leading supporters of Mrs Clinton who on Wednesday had expressed fears that a prolonged campaign might cause “strife within the party”, yesterday appeared reassured after a meeting with the candidate. “Her strategy is to win this,” she said. “And she’s entitled to her opportunity to try.”

A currently unpledged Congressman, Mike Doyle, said: “I think most of us — out of respect for her — are content to wait a little longer.”

Mr Obama is reported to have issued strict orders to his supporters to give Mrs Clinton time and space in which to make her decision. In interviews yesterday he heaped praise on his rival and conceded that she was likely to win the primary in the overwhelming white state of West Virginia next week. But he said that the primaries in Kentucky and Oregon on May 20 — when his campaign expects to reach the 1,627 figure needed for an overall majority of elected delegates — “will be an important day”.

Some members of Mrs Clinton’s inner circle are still determined that she should hang on until May 31, when the Democratic rules committee will decide what to do with the 366 delegates from disputed primaries in Florida and Michigan. Although these results — even if counted in full — would only trim Mr Obama’s delegate lead, they would enable Mrs Clinton to appeal for support from the 250 or so uncommitted super-delegates on the grounds that she was ahead in the popular vote.

Mrs Clinton wrote to Mr Obama yesterday urging him to respect the wishes of the 2.5 million people who voted in Florida and Michigan, saying that otherwise, “whoever emerges as the Democratic nominee will be hamstrung in the general election” — when both states are certain to be key battlegrounds.

With the cover of Time magazine yesterday declaring Mr Obama as the winner there have been suggestions that Mrs Clinton is in denial about her campaign being over.

She dismissed such talk as the latest effort to write her off. It was “déjà vu all over again,” she told crowds.

Some claim that she is fighting on because she wants Mr Obama’s help in paying off campaign debts that are estimated at up to $20 million (£10 million). Others suspect that Mrs Clinton is seeking to strike a deal by which she is given the vice-presidential slot.

This would require Mr Obama to make peace with a woman who is believed to have personally riled him with some of her attacks in recent weeks. But he may yet need to, with deep divisions on class, age and gender — as well as race — opening up within the Democratic electorate during this nomination contest. Exit polls from North Carolina and Indiana showed that half of Mrs Clinton’s supporters would not vote for Mr Obama in the general election in November.

There is also deep bitterness among Democratic activists. A number of bloggers sympathetic to Mrs Clinton are boycotting the popular liberal website, the Daily Kos, because of what they claim is the venomous abuse and hostility from supporters of Mr Obama.

Mr Obama yesterday acknowledged “we have a lot of work to do to bring the party together”. Asked if Mrs Clinton would be his running mate, he replied that such talk was “presumptuous” until the primary process was over, but added: “She would be on anyone’s shortlist to be vice-presidential nominee.”

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