To that end, three months after her husband announced he was running for the Democratic presidential nomination, Obama cut back her hours at the medical center. Logical? Sure. Controversial? That too. In fact, Obama set off a cybersquall of second guessing when she announced that she would work only 20% of the time and she would play her continued employment by ear as the campaign heats up.
"Damn it all, Michelle Obama has quit her $215,000 dream job and demoted herself to queen," ranted an article in Salon.com, whose author described herself as "in a feminist fury."
While political spouse is probably one of America's toughest unpaid jobs, Obama said in a recent interview that she was not surprised by the current debate's ardor, because "we're still struggling with these images of what it means to be a woman." She is comfortable with her choices, she says -- and "God help" those who don't feel the same about their own.
"I know who I am," she said. "I'm a grownup now. Maybe if I were 20 going through this, it would be hard. But these discussions aren't about me. I know why I made my choices. I know what I need to sustain myself, and Barack is the same way."
Obama says she is grounded by her working-class upbringing on the South Side of Chicago, where her father, a Democratic precinct captain, kept track of the boilers for the city's water department until his death from complications of multiple sclerosis in 1990. Her mother stayed at home until Obama was in high school.
Obama's mother still lives in the small brick apartment where her children grew up -- a one-bedroom unit whose living room was trisected by fake wood paneling into bedrooms for Michelle and her brother, Craig Robinson, and a separate space for homework.
Except for Robinson's years at a Catholic high school, the two were products of the Chicago public education system. Their parents never attended college, and Obama often talks on the campaign trail about what a revelation it was when her brother was admitted to Princeton University as a basketball-playing scholar-athlete.
"That was really my first exposure to the possibility of the Ivy League," she said. "It wasn't that I couldn't get in, or I couldn't thrive, or I couldn't survive. I didn't know to want that. That wasn't the vision that I could see for myself because I couldn't see anybody around me doing that."
Obama followed Robinson to Princeton -- a place that "made me far more aware of my 'blackness' than ever before," she wrote in her undergraduate thesis "Princeton-Educated Blacks and the Black Community."
"No matter how liberal and open-minded some of my white professors and classmates try to be toward me, I sometimes feel like a visitor on campus."
Princeton roommate Angela Acree, now a Washington public defender, describes the university in the early 1980s as the kind of place where white students passed by black classmates without a shred of recognition.
"They didn't mean to be rude," she said. "Because they didn't even think they might know a black person, they'd just walk by. All of those things reminded you every single second that you're black, you're black, you're black."
Just as the issue of race was inescapable at Princeton, it is an integral part of campaign 2008.
Barack Obama is the biracial son of a white mother from Kansas and a black father from Kenya, and he has been dogged by questions of whether he is "black enough" on the one hand, and whether America is ready for an African American president on the other.
What his wife brings him is "legitimacy. . . as far as the African American audience" is concerned, said Myra G. Gutin, professor of communication at New Jersey's Rider University and author of "The President's Partner: The First Lady in the Twentieth Century."
And her public comments -- from the bald-faced to the subtle -- seek to dispel racial questions from all sides.
"What are we saying to our children if a man like Barack Obama isn't black enough?" she asked at a Chicago event this month. "Then who is?. . . We have to cut that nonsense out, because it is not helping our children."
There is very little in a Michelle Obama speech that isn't somehow about race, in a presidential contest in which her husband is the most serious African American contender ever to seek the White House.
Race "resonates all through the comments about education," she said in an interview. "It resonates throughout the comments about my upbringing, my childhood, my access to college. It is there. Because it is me."
Time an issue
The Obamas live in a $1.65-million brick mansion with big white columns, multiple chimneys and Secret Service agents parked at the curb in Chicago's storied Hyde Park neighborhood.
In October, they will celebrate their 15th wedding anniversary, just as the run for the Democratic presidential nomination swings into higher gear.