It was a flat crowd who waited for Hillary Clinton in a downtown hotel ballroom on Thursday night, knowing that she had just slipped to third place at the Iowa caucuses and that there was a rollicking party happening down the street at Barack Obama’s event.

Her aides stood, mostly too exhausted to touch alcohol, listlessly scrolling through their BlackBerrys.

Guests gathered in small knots, shaking their heads as they described events at their own caucus meetings.

Catherine Babis, 54, said: “I tried to tell them they should be voting for a president – not an idea – but they wouldn’t listen. It’s a long hard race now, I think, but she will win in the end.”

Her friend disagreed. Cathy Stowe, 58, said that at her caucus in a rural part of Iowa, fellow Democrats “screamed at me, they were nasty”. What did they say? She paused and made a face. “One man said he wouldn’t vote for that bitch Hillary if she was the last person alive. I’m walking away sad and disappointed. I don’t think we can win.”

Many of her precinct captains had met or exceeded their targets for bringing out their core support of middle-aged and elderly women. Most had spent hundreds of hours canvassing in this high intensity battle. But they had been swept away, first by a tide of youthful, idealistic supporters of Barack Obama – and then by the steadfast refusal of others to come to her aid.

Mrs Clinton’s failure could be seen in microcosm at the Precinct 53 caucus at Roosevelt High School in Des Moines on Thursday night where there was a record turnout of more than 350 voters.

Her team had the biggest signs and lots of stickers to hand out. But when it came for caucus-goers to divide into clusters in different corners of the school cafeteria, it was obvious that they were outnumbered by groups for John Edwards and Mr Obama – with the latter so enthusiastic that they kept applauding themselves or whooping.

Supporters of candidates with fewer than 15 per cent of the vote were then encouraged to realign behind one of the the big three.

All but a handful were picked off by the Obama and Edwards groups, with the switchers refusing to cross the room and be seen to support Mrs Clinton.

The Obama team could have denied Mr Edwards a second delegate if they had lent just 12 supporters to a fourth, medium-sized group. But Carl Wiederaenders, the precinct captain, later explained: “We’re honestly not concerned about Edwards. All we want to do is beat Hillary.”

Similar scenes were taking place across Iowa at 1,781 caucus meetings, where second choice votes skewed significantly towards Mr Obama and Mr Edwards: for all the dedication of her supporters, Hillary Clinton is a polarising figure even among Democrats.

Back at her postcaucus party in Des Moines, Mrs Clinton’s aides at the front of the stage were trying to start a “Hillary” chant. Some defiant guests shouted back “New Hampshire! New Hampshire!” – where she hopes to stage a comeback next week.

But one staffer hinted, a little too loudly, that Mrs Clinton’s best hope lay with the bigger states voting on Super Tuesday next month. “February 5! February 5!” he said. “Well, we gotta still believe in something.”

The crowd at last stirred itself into loud cheers when Mrs Clinton arrived. She made a graceful – if low-key – concession speech, declaring herself the “candidate who will be ready to go the distance”.

The campaign may now regret ignoring internal advice six months ago to skip Iowa, which never seemed fertile for her. Instead, she redoubled her efforts here, and Mrs Clinton can at least draw on her deep reserves of unrelenting resolve as she tries to recover her poise over the next month.

It is far to early to write her off. She has consistently led national opinion polls for the Democratic nomination and Mr Obama is braced for a wave of negative attacks in the coming days. Joe Trippi, a senior strategist for Mr Edwards, said: “She is going to kick the living daylights out of Barack.”

But, as she left the party, Mrs Clinton demonstrated a gentler side to her nature. Spotting Ryan Moore, a disabled man in a wheelchair, she threw herself into a lingering and apparently genuine bear hug – pressing her face into his neck. “Ryan, my friend,” she said. “I’m so pleased to see you. You OK?”

Mr Moore afterwards explained that they had met several times over the past 14 years and “she had always looked out for me”. He suggested that her public image was “totally the opposite” of the caring woman he knew. “If only everyone could know what she is really like,” he said. It is, perhaps, a testament to the top-heavy, brittle campaign that Mrs Clinton has run, that more people do not.

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