(CNN) -- While Sen. Barack Obama has campaigned on a message of hope, his wife, Michelle, has talked about the realities of American life -- the gaps between rich and poor, black and white.
Sen. Barack Obama has spoken out against criticism of his wife, Michelle.
She's publicly criticized the United States as "guided by fear" and "just downright mean."
The woman known as "the rock" in the Obama family will now appear before the Democratic National Convention in Denver, Colorado, on Monday -- and before the world -- with a clear message: "One Nation."
But will Michelle Obama -- who could be the nation's first African-American first lady -- carry a theme of unity in light of controversial comments she's made on the campaign trail that resulted in speculation about her patriotism?
Aides in the Obama campaign say she's already honing her message for the fall.
"Michelle wrote her own stump [speech]. And you know, she's refining it now, I think, as we're going into the general election," said Valerie Jarrett, a senior Obama adviser.
"We have an opportunity for her to kind of step back and think about the message she wants to deliver. So she's really working on it as we speak."
Her new speeches will include more details about her family and humble upbringing on Chicago's South Side, aides say.
Michelle LaVaughn Robinson, 44, was born in Chicago, Illinois. She attended Princeton University and then went on to Harvard Law School.
She later became a vice president at the University of Chicago and landed a job as a health care executive making $275,000 a year. Barack, Michelle and their two daughters Malia, 10, and Sasha, 7, live on the South Side of Chicago.
But along with her success has come criticism.
Robin Givhan, fashion editor with The Washington Post, told CNN that people see Michelle Obama in different ways.
"Some people will see confidence, and others might see cockiness. I think some people will see strength. Others might see arrogance," she said. "She comes across as someone who is extraordinarily independent and very much a force to be reckoned with."
Behind the scenes, she maintains that independence. But with the election just months away, the potential first lady is trying to connect with voters on a more personal level.
In June, she made an appearance as a guest co-host on ABC's "The View," and later, she and her husband graced the cover of Us Weekly.
The magazine, headlined "Michelle Obama: Why Barack Loves Her," included details about her love for Target, "Sex and the City" and her daughters' recitals.
Asked on "The View" if she's going through a makeover, she said she realizes that "I wear my heart on my sleeve" and that "it's a risk you have to take." She said she thinks people will change their perception of her as they see her family more.
Carl Sferrazza Anthony, a first ladies historian, told CNN that it's important for Michelle Obama to define herself before others define her.
"One comment made off-hand ... might be easily misinterpreted by the opposition," he said in June.
Michelle Obama saw that in February when a Tennessee Republican ad used a snippet from a campaign event in Milwaukee, Wisconsin. There, while referring to record voter turnout in the Democratic primaries, she said, "for the first time in my adult lifetime, I am really proud of my country."
The Obama campaign called the ad "shameful," and it was condemned by the state's two Republican U.S. senators.
But the ad's message caught on in conservative blogs -- and later forced Michelle Obama to clarify her remarks.
"What I was clearly talking about is that I am proud in how Americans are engaging in the political process," she responded. "I mean, everyone has said what I said, in that we haven't seen these record numbers of turnouts, people who are paying attention, going to rallies, watching debates."
Cindy McCain, the wife of Sen. John McCain, the presumptive Republican presidential nominee, also took a shot at Michelle Obama at the time, saying, "I am proud of my country. I don't know about you, if you heard those words earlier. I am very proud of my country."
More recently, controversy erupted over a July 13 New Yorker magazine cover showing Barack Obama in the Oval Office dressed in traditional Muslim attire, and Michelle Obama with an Afro hairstyle and a machine gun slung over her back. An American flag can be seen burning in the fireplace, and a picture of Osama bin Laden hangs on the wall.
Shortly after the magazine was published, Obama campaign spokesman Bill Burton called the cover "tasteless and offensive." John McCain later said it was "totally inappropriate."
But the overall issue of Michelle Obama as a potential liability has made headlines on both coasts -- with articles in both The New York Times and the Los Angeles Times in early June.
The newspapers pointed to relentless online rumor mills, criticism on conservative blogs and articles in conservative magazines, like the National Review, critical of Michelle Obama.
New York Times columnist Maureen Dowd wrote in June that the backlash against Michelle Obama was a "good preview of how Republicans will attack Michelle, suggesting that she does not share American values, mining a subtext of race."
Conservatives view the presumptive Democratic nominee's wife as a target of opportunity. But one Republican consultant has said attacks on candidates' wives often backfire.
"Considering there are so many issues -- legitimate issues -- that you can use on Barack Obama, to attack his wife to me is sheer utter stupidity of the highest level," Stephen Marks, a Republican strategist, told CNN in June. "Mr. Obama is going to come to his wife's defense, and it's going to humanize both of them."
Republican strategists say the wife of the Democratic presidential nominee is fair game.
"There is less information about him to temper her comments against, so what she says represents something a lot more important than perhaps other candidates in the past who have had a longer track record," Rachel Marsden, a Republican strategist, also told CNN.
The potential first lady, however, appears to be bracing for what may lie ahead.
"We're trusting that the American voters are ready to talk about the issues and not talking about things that have nothing to do with making people's lives better," Michelle Obama told ABC News during a joint interview in May.
But Barack Obama quickly added, "I also think these folks should lay off my wife."
CNN's Randi Kaye and Jonathan Mann contributed to this report.