US:Hillary Clinton's rivals for the Democratic presidential nomination were hoping yesterday that a debate in Philadelphia on Tuesday that saw her come under relentless attack from other candidates could mark a turning point in the campaign.
Flawless performances in earlier debates helped build Mrs Clinton's massive lead in national opinion polls and in most early voting states.
However, Tuesday's two-hour debate was dominated by criticism of the frontrunner for what other candidates claimed was her eagerness to tack to the political wind on everything from the war in Iraq and the possibility of an attack on Iran to reforming America's pension system and embracing free trade.
Barack Obama declared in advance of the debate that he was ready to take a more aggressive posture towards Mrs Clinton but it was former senator John Edwards, who is in third place in the polls, who struck the most powerful blows.
Mr Edwards said that Mrs Clinton's vote for a senate resolution calling for Iran's Revolutionary Guards Corps to be designated a terrorist entity could give President George Bush a pretext to attack Iran.
"A lot of us on this stage have learned our lessons the hard way, that you give this president an inch and he will take a mile," Mr Edwards said.
"We need to make it absolutely clear that we have no intention of letting Bush, Cheney or this administration invade Iran because they have been rattling the sabre over and over and over."
Mrs Clinton said the senate resolution gave no authority to the president to go to war against Iran, adding that she hopes to introduce a new resolution declaring that economic sanctions and diplomacy are the way to deal with Iran.
"I am not in favour of this rush for war, but I'm also not in favour of doing nothing. Iran is seeking nuclear weapons. And the Iranian Revolutionary Guard is in the forefront of that, as they are in the sponsorship of terrorism," she said.
"I prefer vigorous diplomacy. And I happen to think economic sanctions are part of vigorous diplomacy. We used them with respect to North Korea. We used them with respect to Libya."
The debate saw criticism of Mrs Clinton that has until now been channelled through background briefings by campaign staff burst into the open.
Mr Obama accused her of dishonesty and secretiveness, pointing to former president Bill Clinton's demand that records of communications between himself and his wife in the White House should remain sealed until 2012.
"We have just gone through one of the most secretive administrations in our history. And not releasing, I think, these records at the same time, Hillary, that you're making the claim that this is the basis for your experience, I think, is a problem," Mr Obama said.
Mrs Clinton, who smiled much less and appeared more tense than in earlier debates, fought back skilfully against most of the criticism, turning her fire on the Bush administration and the Republicans rather than on her Democratic rivals.
In the final minutes of the debate, however, moderator Tim Russert asked her if she backed New York governor Eliot Spitzer's plan to issue driving licences to illegal immigrants in her home state of New York.
"I did not say that it should be done, but I certainly recognize why Governor Spitzer is trying to do it," Mrs Clinton said.
"It makes a lot of sense. What is the governor supposed to do?
". . . do I think this is the best thing for any governor to do? No." Mr Edwards and Mr Obama almost fell over one another as they pounced.
"Senator Clinton said two different things in the course of about two minutes just a few minutes ago, and I think this is a real issue for the country . . . America is looking for a president who will say the same thing, who will be consistent, who will be straight . . .", Mr Edwards said.