RACINE, Wis. — As the music of Stevie Wonder pulsated through Racine Memorial Hall, Michelle Obama bounded onto the stage.
"You know what this room feels like? It feels like four more years in here!" the first lady exclaimed as the crowd of 2,500 roared its approval. The audience, including some who had waited overnight to see her, thundered again after Mrs. Obama noted that Racine is just 80 miles north of her hometown.
Until the election, she said, "coming here to Racine is the closest thing I'm going to get to be at home in Chicago."
Her husband's campaign is dispatching her to critical battleground states, high-profile appearances and big-money fundraisers. Her stepped-up schedule, packed with mostly campaign events these days, is a sign of the tight race between President Barack Obama and Republican Mitt Romney and the Obama campaign's belief that the first lady is a valuable asset.
Mrs. Obama, whose favorability ratings are higher than her husband's, can make the case for his re-election in a way no one else can, said Anita McBride, who served as Laura Bush's chief of staff in the White House.
"The first lady is always good for a couple of important things," McBride said. "One is the human side of the president, seeing who they are personally through the lens of the spouse, which is always unique."
First ladies also can champion the idea that "my husband is fighting for you" in a way that even the president and vice president cannot, McBride said.
The first lady's 35-minute campaign speech mixes the personal and political, offering glimpses of life in the White House and some of the reasons she married the president, along with an impassioned defense of his policies and character.
Most of all, she beseeches crowds to get out and vote and urge their friends and family to do the same.
"This election will be closer than the last one. That's the only guarantee. And it could all come down to just a few battleground states like right here in Wisconsin," Mrs. Obama said.
McBride called Michelle Obama a skilled campaigner who is much more enthusiastic this time around than in 2008, when she initially appeared reluctant to speak out on behalf of her husband.
"She never loved the political game and she was honest about that" in 2008, McBride said. But this year, "she is comfortable on the stump. She brings a lot of energy and she is in it to win it."
While Obama won Wisconsin handily in 2008, the state could be decided by just a few thousand votes this year, the first lady said. It may sound like a lot, she said, but those votes are spread across the state and hundreds of cities and towns.
"So when you break down those numbers, it turns out that just a handful of votes in every ward could make all the difference in the world," Mrs. Obama said. "So that one neighbor you get to the polls, that one voter you register and persuade, that one volunteer that you recruit, understand that will be the one that puts us over the top."
The Wisconsin visit followed campaign appearances in North Carolina and Ohio and earlier visits to Colorado and Virginia — all battleground states. She also taped an appearance on "Live! With Kelly and Michael" and flew to New York for two fundraisers that brought in hundreds of thousands of dollars.
She heads to Hollywood on Thursday to appear on Jimmy Kimmel's late-night TV show and raise money with actor Will Smith.
Jeremy Bird, national field director for the Obama campaign, said Michelle Obama is a valuable "grass-roots champion" in early voting states such as Wisconsin. She heads the campaign's "It Takes One" program, which urges supporters to do one thing to promote the campaign — and to engage someone else to do likewise.
"Your vote matters in places like North Carolina and Ohio and Wisconsin," Bird said, adding that the first lady stresses the importance of volunteer efforts to push people to vote and generate enthusiasm for the campaign.
In Racine, Mrs. Obama repeatedly engaged the audience in a friendly, even intimate way. One of her favorite parts of the campaign is being able to praise her husband without him hearing, she told the crowd: "So don't tell him how much I really love him. I kind of keep that leverage. That's between you and me."
Outlining her husband's efforts to rebuild the economy, she said manufacturers have added 500,000 jobs. "Do you hear me?" she asked, one of 11 times she used the phrase.
Interviews with voters produced enthusiastic reviews. Nearly all used the same word: "inspiring."
"I'm ready to go to work," said retiree Melissa Warner, of Caledonia, Wis. A member of the Sierra Club, Warner said she will volunteer at phone banks for the environmental group and the Obama campaign.
Shanon Molina, 32, of Kenosha, Wis., also was ready to volunteer. She said her favorite part of the speech was when the first lady said, "Don't let anyone talk down your dreams."
"I put that on Facebook" even before the speech ended, Molina said.
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