Barack Obama plucked a crucial endorsement from his rival Hillary Clinton yesterday and side-stepped a series of attacks before last night's televised debate in Ohio.
For the first time in the presidential campaign, Mr Obama went into the lead in a national poll with 54 per cent Democratic primary voters supporting his nomination against 38 per cent for Mrs Clinton, a lead greater than the pollsters' margin for error of plus or minus 5 per cent.
In Ohio and Texas, where there are primaries next Tuesday, the race is neck and neck, and Mrs Clinton is holding on to a narrow lead in rustbelt Ohio. She is now under enormous pressure to win, with no less a figure than Bill Clinton stating that she must capture both states to stay credible in the race for the Democratic nomination.
Last night's televised debate was Mrs Clinton's last opportunity to slow her rival's growing momentum. But even as she flailed at her opponent beforehand, throwing what a campaign member described as "the kitchen sink" at him, there was more bad news when the former Democratic contender Chris Dodd came out for her opponent. "He's ready to be president and I am ready to support him in this campaign," Mr Dodd said at a joint news conference with Mr Obama.
Mr Dodd, 63, pulled out after doing poorly in the Iowa caucus last month, and his endorsement has been sought by both camps. The blow will be all the more painful because of his long-standing ties to both Clintons.
The obstacles she faces are daunting. The polls show that Mr Obama's appeal has expanded far beyond his original coalition of Democratic "dreamers", reform-minded wealthy voters, young people and blacks. Since December, the number of men supporting his campaign has grown from 26 per cent to 67 per cent. Mrs Clinton's support among men has collapsed to 28 per cent.
Mr Obama's campaign has also been buoyed by a strong showing in the polls, with Democrats now seeing him as the best placed candidate to beat the Republican, John McCain, in November's general election. His support base has expanded to include a broad coalition of voters: men and women, rich and poor, university graduates and the less educated.
Mrs Clinton has tried a variety of tactics to blunt the Illinois senator's advance, first denouncing him for not being protectionist enough in a campaign flier, then ridiculing his message of hope as naive. On Monday, she was on the offensive again, comparing his lack of foreign policy experience to George Bush's lack of experience when he was first elected president.
"We've seen the tragic result of having a president who had neither the experience nor the wisdom to manage our foreign policy and safeguard our national security," Mrs Clinton said. "We can't let that happen again."
The former first lady's dilemma is that by going negative so late in the campaign she may alienate voters in two primary elections that are expected to be tight.
The only hope for the Clinton campaign came in the latest New York Times polls, which showed she is considered to be better prepared for the job of president and has more support among women. The surveys showed her rival was supported by two-thirds of men and 45 per cent of women. But single, white women remain Mrs Clinton's most loyal supporters.
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