She admonishes her husband's Republican critics, and tries to convince woman that Mitt Romney is on their side. She also counters the portrait her husband's opponent paints of a soul-less corporate raider, and seeks to show his softer side, like she did Tuesday when she recalled how he made regular visits in the 1970s to a 14-year-old who was dying of cancer, even helping the boy write his will.
"That is where Mitt is when someone's in trouble, he's there, he's by the bedside," Ann Romney told a crowd at a park in this vote-rich area as her husband stayed out of sight ahead of Wednesday's debate. "Right now the country's in trouble. We need someone who cares, who truly understands what is going on."
In the weeks since her big convention debut, she has become the center of a campaign within the campaign. She has her own charter airplane, holds her own fundraisers, campaigns at her own events, and often sits down for more local interviews than her nominee husband does. On Monday, she held an event in Henderson, Nev., competing with President Barack Obama, who was in town to prepare for his head-to-head matchup with Mitt Romney. After her Tuesday appearance, she did three interviews with local stations.
It wasn't always this way.
While she frequently appeared alongside Romney earlier this year, Ann Romney didn't really venture out on the trail on her own much. The campaign had been careful how it deployed her, mindful that she has multiple sclerosis. Her disease flared during the stressful campaigning of the primary season, right before voting on Super Tuesday. It was a reminder of her need to stay rested.
Her husband has told donors that the campaign was worried about her facing too much criticism early in the campaign.
"We use Ann sparingly right now, so that people don't get tired of her, or start attacking," he said in May at a Florida fundraiser that was captured on tape and published by the magazine Mother Jones. "But you will see more of her in the September, October timeframe."
He also made reference to Democratic strategist Hilary Rosen, who said earlier this year that Ann had "never worked a day in her life," sparking an outcry from Republicans who defended stay-at-home mothers.
"That made Ann much more visible to the American people, which I think is very helpful. It gave her a platform she wouldn't have had otherwise," Romney said.
Her biggest appearance to date came at the GOP convention in Tampa, Fla., as she spoke in greatly personal details about the man she's been married to for four decades and made a direct pitch to a group of voters with whom Obama has an edge in polling.
"I love you women! And I hear your voices," she said, delivering a forceful defense of her husband's character and values in a speech designed to introduce the country to the man she knows better than anyone.
Since then, Ann Romney has ended up defending her husband in a myriad of ways, whether from people who suggest he doesn't understand the concerns of average Americans to sniping within the Republican Party.
In Denver on Tuesday, a KUSA-TV viewer asked whether she and her husband really have a finger on pulse of Americans if they've never struggled.
"Struggle is an interesting thing," Ann Romney responded. "I can tell you Mitt and I have struggled a great deal, that we can understand people who are going through difficulties right now because we have gone through our own personal hardships. You don't have to struggle in exactly the same way to have compassion for others. And if you look at the measure of who he is, how generous he has been his entire life and helping others, you have to know that this guy does care."
Last month, as second-guessing of her husband reached a new height following the release of a secret recording of one of his fundraisers, she made her most pointed statements to date, addressing critics of his campaign.
"Stop it. This is hard. You want to try it? Get in the ring," she said during an interview with Radio Iowa. "This is hard and, you know, it's an important thing that we're doing right now and it's an important election and it is time for all Americans to realize how significant this election is and how lucky we are to have someone with Mitt's qualifications and experience and know-how to be able to have the opportunity to run this country."
And asked in a separate interview what she was most concerned about should her husband win the presidency, she said she worried for his emotional state.
"My biggest concern, obviously, would just be for his mental well-being," she told a Nevada TV station last week. "I have all the confidence in the world in his ability, in his decisiveness and his leadership skills . So for me I think it would just be the emotional part of it."
Ann Romney has long been pivotal to the campaign's outreach to female voters, pointing out how she talks to her husband about the concerns they have amid a struggling economy. But she has been careful not to step into hot-button debates.
Last month she declined to answer a question about gay marriage from Iowa KWQC anchor David Nelson. He later asked: "Do you believe that employer-provided health insurance should be required to cover birth control?"
Ann responded: "Again, you're asking me questions that are not about what this election is going to be about. This election is going to be about the economy and jobs."
On Tuesday, Ann steered clear of specific policy debates, instead offering warm testimonials to her husband.
Carole Clark, 72, was impressed.
"She's first lady material. God bless her," Clark said. In contrast to Mitt Romney, Clark added, "She's a little bit easier with the crowd."