Tall, slim and elegant, Michelle Obama gracefully acknowledges the deafening, foot-stamping ovation with which 1,000 North Carolinian baptists greet her at their annual convention in this military town, then launches into a stump speech unlike any other in this presidential election year.

She speaks of her parents – the “warmest hardest-working people I have ever known”. She talks of her two daughters – Malia, 10, and Sasha, 7 – who are “God’s greatest gift to me”. And, of course, about her husband – how his life has equipped him to address the problems of struggling Americans, and why he would make an extraordinary president. “Barack Obama gets it,” she declares.

It is a disciplined, well-rehearsed speech that contains no red meat to incite her audience, no mention of her husband’s opponents, no detailed policy statements – nothing that might grab headlines. On the contrary, it is designed to calm, assuage and reassure not so much this audience, for it is almost entirely black, but the country at large.

This is, after all, the woman who aspires to be America’s first black First Lady – and in Mrs Obama’s case “black” means wholly black. Unlike her “postracial” husband, son of a white mother and Kenyan father who came to America as a student, Mrs Obama is the descendant of slaves on both sides of her family and was raised in Chicago’s overwhelmingly black South Side.

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This year – during the primaries – Mrs Obama was in danger of becoming a liability to her husband’s campaign with her unguarded pronouncements. “For the first time in my adult life I am proud of my country,” she declared. “If we lived anywhere else on the planet, a man with the credentials and commitment and the ability of Barack Obama – we wouldn’t have any questions,” she protested. America was “just downright mean”, she proclaimed.That abrasive, polarising Mrs Obama has long gone, replaced by a woman who now presents herself as “Mom-in-chief” to two girls who would be the youngest inhabitants of the White House since Amy Carter in 1976.

Though her campaign speech dwells on the problems faced by ordinary Americans, it is mostly warm, optimistic, feel-good fare. She travels in a small chartered jet with a few aides and secret service agents, but no press corps. She gives interviews only to magazines such asGood Housekeeping or People, or to television hosts such as Larry King or Jay Leno who do not subject her to political interrogations.

These interviews elicit plenty of snippets about Obama family life – the girls’ strict 8.30pm bedtime, the no-jumping-on-the-sofa rule, buying lavatory paper at Target, her husband’s favourite meal (shrimp linguini), his domestic shortcomings (not making the bed or putting his dirty laundry in the basket), and how he interrupted his campaign to fly home and take her out to dinner on their wedding anniversary. The subliminal message is: “We’re just like you.”

She happily discusses how she juggles campaigning and motherhood, and tries to be home for her daughters’ bedtime and their weekend piano, ballet and soccer sessions.

Mrs Obama adroitly avoids questions on contentious issues such as race. Asked about Republican advertisements attacking her husband, she replies: “Fortunately, we’re just too busy to watch this stuff.” She even expresses understanding of Sarah Palin’s wardrobe problem and speaks warmly of the “pitbull in lipstick” who regularly savages her spouse: “I think she provides an excellent example of all the different roles a woman can and should play.”

This may sound demeaning for a high-powered lawyer who was raised in a working-class home in a tough Chicago neighbourhood, went to Princeton and Harvard Law School and is now a senior hospital executive. But it is effective. Mr Obama’s recast wife is now one of his greatest assets and most effective cheerleaders.

Her domestic anecdotes help to humanise the man she calls “my honey” and “babe”, and undercut Republican charges that he is a closet radical who consorts with terrorists. “My job is to make sure people know the Barack Obama I know,” she says.

Furthermore, the picture she presents of a loving but disciplined household offers a subtle contrast to Mrs Palin’s rather disorderly, rough-and-ready family life in Alaska and her pregnant teenage daughter.

Mrs Obama is undoubtedly a devoted mother and spouse, but in truth she is no more a Stepford Wife than she is an angry black radical. She insists that she would not want a West Wing office or major policymaking role in the White House, and would focus on women’s issues, but the idea that she will be a passive, ornamental First Lady if her husband wins next Tuesday is a stretch to say the least.

As her carefully calibrated campaign appearances suggest, Mrs Obama is far too ambitious and intelligent; too savvy and political for that.

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