Hillary Clinton suffered the worst 24 hours of her presidential campaign yesterday after a prime-time debate in which she was accused of giving dishonest answers.

Mrs Clinton came under such relentless attack from her Democratic rivals that her aides blamed the debate moderator for allowing them to gang up on her, a response that undercut the image of strength and invincibility that she has so carefully cultivated.

Mrs Clinton, the Democratic frontrunner, was the target of almost constant attack by her main rivals, who know that time is running out to halt her march to the nomination. For the first time they said outright that she was unelectable.

Her worst moment came just before the end of the two-hour debate, when she equivocated over whether she supported a plan in New York to give illegal immigrants driving licences. The response allowed rivals to paint her as evasive and dishonest, claims that have powerful resonance after the scandals of her husband’s presidency.

John Edwards, lagging third in national polls, capped an overtly aggressive evening when he said of her refusal to say whether she was for or against the driving licence plan: “Unless I missed something, Senator Clinton said two different things in the course of about two minutes, and I think this is a real issue for the country.” At another point, Mr Edwards said that Americans deserved a president who would tell them the truth.

Barack Obama, her leading rival, had said in a weekend interview that he was going to change tactics and challenge Mrs Clinton aggressively. Although he criticised her frequently he was often overshadowed by Mr Edwards, leaving a growing number of his supporters believing that he lacks the ruthlessness required to win.

Mrs Clinton stuck to her strategy of ignoring rivals and attacking Mr Bush, whom she mentioned 25 times. She denied claims that her hawkish stance on Iran was helping the President to prepare for a military strike. She said that Republican obsession with her was proof that she had stood against President Bush and his “failed policies”. Mr Obama and Mr Edwards said that the Republican presidential candidates invoke her so often because she is the candidate they want to run against. Chris Dodd, a long-shot Democratic candidate, was more blunt. “There are 50 per cent of the American public that say they’re not going to vote for her.”

Aides to Mrs Clinton’s rivals claimed yesterday that Tuesday night’s debate revealed the first significant cracks in her campaign, and proved that she was far from invincible only two months before the first votes were cast in Iowa. They said that they would use the issue of evasiveness and unelectibility as the main lines of attack in coming weeks and believe they are true vulnerabilities.

Mrs Clinton’s occasionally wobbly performance generated such excitement inside the rival campaigns only because it reflects how starved they have been of any mistakes by her to exploit. She has run the best campaign and is still the frontrunner with the best political machine in America.

This was the Democrats’ seventh debate. Political pundits analyse every thrust and parry but it is unclear how closely they are watched by voters. Although Mrs Clinton leads her nearest rival, Mr Obama, by at least 24 points, they are tied in Iowa, which votes on January 3. A victory by Mr Obama there, or by Mr Edwards, could alter the dynamic of the race.

Running total

Democrat voting intentions:

Clinton 45.7%
Obama 21.7%
Edwards 12.9%

Source: RealClearPolitics.com, polling average

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