(CBS News) CHARLOTTE, N.C. -- On the opening night of the Democratic National Convention, First Lady Michelle Obama shared the intimate stories of her life with her husband, President Barack Obama, to convince voters that his work as president is motivated by personal convictions, not by politics.
"Today, after so many struggles and triumphs and moments that have tested my husband in ways I never could have imagined, I have seen firsthand that being president doesn't change who you are - it reveals who you are," Mrs. Obama said. "I've seen how the issues that come across a president's desk are always the hard ones... But at the end of the day, when it comes time to make that decision, as president, all you have to guide you are your values, and your vision, and the life experiences that make you who you are."
The first lady recounted Mr. Obama's modest beginnings in Hawaii, where his grandmother worked to support him. She also shared her own background, growing up middle class in Chicago, where her father struggled with Multiple Sclerosis (a disease that also happens to plague Mitt Romney's wife Ann Romney). Mrs. Obama recalled her first dates with Mr. Obama, when he was so poor that his "only pair of decent shoes was half a size too small."
And Mrs. Obama recounted the first years of their marriage when, after years of bills for their higher education piled up, she said, "We were so young, so in love, and so in debt."
The first lady told the audience of Democratic delegates that, four years ago, she was afraid that her husband would change in office. Instead, she learned that his work was driven by that personal history.
"He's the same man who started his career by turning down high paying jobs and instead working in struggling neighborhoods where a steel plant had shut down, fighting to rebuild those communities and get folks back to work," she said, "because for Barack, success isn't about how much money you make, it's about the difference you make in people's lives."
The first lady made no mention of Mr. Obama's GOP rival Mitt Romney, but her characterization of her husband as a man who put his ideals before material success sets up a contrast with the former corporate CEO, whom the Obama campaign is attempting to cast as a heartless businessman. With a struggling economy weighing down Mr. Obama's re-election chances, the president will have to appeal to voters as a politicians who empathizes with their problems, even if he hasn't fixed them all quite yet.
"Barack knows what it means when a family struggles," she said. "He knows what it means to want something more for your kids and grandkids."
Because of his own family's hopes and challenges, the president reads with concern letters from struggling Americans, Mrs. Obama said. "I hear the determination in his voice as he tells me, 'You won't believe what these folks are going through, Michelle...it's not right. We've got to keep working to fix this. We've got so much more to do.'"
Mrs. Obama also spoke of her own experiences hearing Americans' stories as she traveled across the country. "I have seen the very best of the American spirit," she said. "I've seen it in teachers in a near-bankrupt school district who vowed to keep teaching without pay... I've seen it in our men and women in uniform and our proud military families. In wounded warriors who tell me they're not just going to walk again, they're going to run, and they're going to run marathons."
As first lady, Michelle Obama spearheaded initiatives to help veterans and their families. Ahead of her speech, her brother Craig Robinson took the stage with Mr. Obama's sister, Maya Soetoro-Ng, and touted her accomplishments.
"Four years ago, I told you how, when she was a young girl, Michelle used to talk to me about which kids at school were having a tough time at home and didn't have anybody to stick up for them," Robinson said. "And what inspired her most as she traveled this country on that campaign were the stories of brave Americans who juggle everything at home while their husbands or wives are off at war."
Robinson and Soetoro-Ng reiterated Mrs. Obama's assertion that the Obamas' beliefs are rooted in strong values.
"But no matter how different we may seem," Robinson said, "we share a set of values our parents gave us--values the same in Chicago as they are in Honolulu: a willingness to work hard, a commitment to education and the responsibility to look out for each other."