Michelle Obama: "We Have so Much More in Common in This Country"

First lady Michelle Obama stands during a soundcheck on Monday, Sept. 3, in preparation for the Democratic National …As she prepares to speak tonight at the Democratic National Convention in Charlotte, North Carolina, First Lady Michelle Obama says that her goals for the 2012 election campaign are much the same as they were in 2008.

"Four years ago, millions of people across this country came together and elected the leader they knew would stand up for them in office," she told Yahoo! Shine in an interview hours before her speech. "I want people to know that Barack is still that leader. He is still driven by the core values and principles that made him want to do the incredibly tough job in the first place."

WATCH: First Lady Michelle Obama and Dr. Jill Biden talk to Yahoo! Shine about military families

Since becoming the first lady, Mrs. Obama has honed her speaking skills and sharpened her focus. Though people still criticize her for comments made in the last election cycle (particularly the one about finally feeling proud of her country), she has largely avoided controversy, focused on family issues like combating childhood obesity and supporting military families, and now has far more fans than political foes. And, after four years in the spotlight, she has learned how to reach her core audience.

"As first lady, I have been fortunate to have the opportunity to meet some really amazing people from all over the country," she said during a conference call on Tuesday. "Getting to meet those people, that's really one of the most meaningful parts of being first lady. Getting to meet folks of all walks of life and all backgrounds, because the stories that they have shared with me, they've really inspired me and really kept me focused. They remind me of what Barack says again and again, that we have so much more in common in this country than we do the differences that we all talk about."

Pre-Convention tussle: Are Americans better off?

Some of the moments that stand out for her over the past four years in the White House dovetail neatly with the message she hopes to share at the Democratic National Convention.

"I've had an up-close look at just how hard Barack has worked to move this country forward, to rescue our economy, and rebuild our middle class, to give our kids the opportunities they deserve," she said. Americans are better off than they were just four years ago, thanks to the passage of the Affordable Care Act and the signing of the Lilly Ledbetter Fair Pay Act, among other things. "Women's success in this economy is the key to family success in this economy," she said, adding that fair pay and access to health care are more than "just women's issues."

"They're really family issues. They're basic economic issues that affect our kids and our communities and our entire country," she said. "In this election, we as voters are going to determine whether we want to keep these reforms and all these accomplishments, or whether we're going to watch all of this be repealed, and turn back all of the progress we have made."

As she learned from her husband's last campaign experience, political controversy tends to gather more attention than personal conviction. "Sometimes, it's important for people to remember who this man is in terms of his values and convictions and his character," she explained.

"This speech has given me an opportunity to reminisce about our lives together, how he grew up, how both of our upbringings have affected who we are as people today, specifically for Barack and how it affects his policy decisions and everything he does," she said. "That's why he's always focused on building the economy from the middle class out. Because we were both raised in working families, and we understand the challenges that come when folks are out of work and the economy is struggling, we understand that that is the backbone of this country, it's working class folks like my dad and his grandparents who really make this country strong."

"We get lost in the political back and forth that goes on with some of these issues, and we forget that in the end there are real people whose lives hang in the balance," she added.

The first lady will speak at the convention tonight at 10:35 p.m. EDT (you can watch it at Yahoo.com.) The President said that he and their daughters will watch from the White House.

"I'm going to try to not let them see their daddy cry because when Michelle starts talking, I start getting all misty," Obama said at rally in Norfolk, Virginia.

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