ON the eve of a campaign visit to Britain, the wife of Barack Obama, the Democratic presidential contender, has delivered a spirited warning to Hillary Clinton, his toughest rival.

“Nothing is inevitable,” said Michelle Obama, vowing that her husband was a “uniter” who could beat Clinton to the party nomination.

Asked if she thought Clinton was a polarising figure, she replied: “That is definitely one of the challenges she faces. You can see it in the surveys.”

In an interview with The Sunday Times, she said that her husband had the magic to defeat the Clintons’ machine even though he was behind in the polls.

“People know Hillary and Bill, so their first instinct is to say: well, I’ve heard of these people,” she said. “But the more people see Barack, the more they like him. His favourable ratings are higher and, to top it off, he has brought in more money than any other candidate from a broader base of support.”

Drawing an explicit contrast with Clinton, she said: “The ‘inevitable’ candidate has not raised the most money and doesn’t have the biggest base of donors . . . So where’s the ‘inevitability’?”

She implicitly likened the rival campaign to a familiar but faded outfit at a time when America needed a fresh approach. “There is a choice we can make. It is a little scary because change is scary. Americans are creatures of habit,” she said.

“Sometimes we wear the same suit even if it’s got holes in it. We need a new suit, not just a new tie or new pants.”

Michelle Obama, 43, is an attractive and eloquent advocate for her 46-year-old husband. At 5ft 11in she has the looks of a model, but she is also emerging as a feisty campaigner.

She made it plain that they had no intention of letting Clinton walk over them. “A lot of times we’ve had leadership that has played on the divisions in this country, but the core values that unite us are real.” She thinks the key to victory lies in early primary states, where voters are seeing her husband close up. Obama, she claimed, was “neck and neck with one of the toughest political dynasties that we’ve seen in my lifetime”.

She added proudly: “The Clintons were supposed to be able to out-organise us. They haven’t . . . We’re building a grassroots movement of people and have an organisation that is unmatched in the early states.”

Michelle Obama will be the star guest at a $100-a-head “Obama for America” fundraiser in London tomorrow – a sign that her husband’s team is creatively targeting every possible source of revenue, including affluent Americans abroad. “We talked about whether I could go to the theatre or maybe shop, but it will just be one day in and out,” she said.

Then it will be back to Chicago’s South Side to daughters Melia, 9, and Sasha, 6, and a new round of campaigning.

“When I walk into a roomful of people, the purpose of what we’re doing takes hold in my mind and I’m energised and ready to go,” she said. “I really enjoy it. You have the privilege of being reminded just how decent people are.”

The sheer competence of the Illinois senator’s organisation initially caught Clinton’s camp off-guard but her veterans have recovered their poise.

Both candidates have raised nearly $80m each for the presidential race, a record-shattering sum, although Obama has raised more for the primary campaign from nearly 350,000 donors.

Yet Clinton has moved into a commanding 21-point lead over Obama in the opinion polls. In Iowa, an early voting state, Clinton holds just a three-point lead but the dial appears to be shifting in her direction.

The Obamas are sharpening their critique. Barack Obama has condemned Clinton for handing Bush a “blank cheque” for war after she voted to designate the Iranian Revolutionary Guards a terrorist organisation. It was a repeat, he suggested, of her vote to authorise the use of force in Iraq. “Now is the time that we’re going to be laying a very clear contrast between myself and Senator Clinton,” he told CNN.

Obama’s greatest appeal, his wife said, was that he was a “uniter, not just here but globally”. The process of democracy did not have to be “caustic”, she added: “You can disagree without being disagreeable. Barack has built his entire success in politics on this strategy.”

Obama has a vision of “who we want to be”, she said. “That’s the excitement he taps into and where his energy comes from. We’ve settled so much in this country for less than we want because we think that’s all there is.

“The thing Barack and I stay focused on is what we think politics should truly be in this country, words like honesty and truth-telling and getting to the point where leaders tell us what they really think, even if it’s not what we want to hear.”

It was a staunch tribute from a wife who has sometimes been criticised for joking that her husband does not always pick up his socks or is too “snorey and stinky” for his daughters when they sneak into bed for a cuddle.

She is proud that their daughters have a happy home life. “When we entered the race, Barack and I said there is a way to do this and keep the kids sane and stable. It requires a lot more juggling but it’s worth it. They are very confident about who they are, and that they are still the centre of our universe.”

If Obama wins the presidency, his wife will be the first African-American first lady. She is concentrating on “getting through the days” rather than making history she said. But she allowed herself one tempting thought. “If Barack becomes the next president of the United States, I’ll be in Britain often!”

Find out details of Michelle Obama's visit to London at the Obama abroad website

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