"When we talk to you about the 2014 elections..that's what's at stake,'' she said. "We cannot forget that."
"We need to ask ourselves whether we will have leaders in congress who share our values,'' she said.
"That is why the midterm elections are so critical,' she said, adding that she will continue to travel the country "talking about the midterms, galvanizing energy and passion."
Mrs. Obama said that she wants to support values that say "if you're wiling to work for it..you should be able to build a better life for your kids, our kids.''
Of course, she said, no one should "get a free ride,'' but Americans should also remember -- "There but for the grace of God go I."
"Any of us could lose the job we count on to support our family..and when that happens, it shouldn't mean falling off the cliff...not here in the United States of America ... that's not who were are."
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"We also believe that we should give everyone a fair shot,'' she said. "And that's certainly the kind of security..that I know so many of you grew up with."
"My family wasn't rich, far from it,'' she said. But she said she had "decent public schools,'' a supportive family, and her father had a good job.
"So I was able to get a college degree and go on to law school."
"For a working class kid from the South side of Chicago, being able to get my education meant everything to me...it was the foundation of my career. it was the launching pad for my dreams."
Today, there are so many kids out there, just like me, just like Barack..with such big dreams and so much promise -- kids who will never get those opportunities."
"For so many of these kids, no one is willing to invest in them,'' she said. "No one helps them shape a vision for what their lives could be with a decent education...and what's even worse is that when we fail to invest in our young people...it limits our country's future as well."
She said every day she thinks about "the millions of kids who fall through the cracks of opportunity" in this country.
"My story can be their story, if we give those kids a chance,'' she said.
She said she and the president will work to help more kids get to college, "so that they can pass on that gift of opportunity to their kids."
But she added:
"Barack cannot do all of this alone, just sittin' by himself in the Oval Office. It's a lonely place,'' she said to laughs.
She urged them to remember the Recovery Act, which created millions of jobs, and the Lily Ledbetter Fair Pay Act, to help women "get equal pay for equal work."
"And of course,e there's the Affordable Care Act,'' also passed by Congress.
"So it matter who we elect in Washington...and right now we are just 17 seats away from winning the House of Representatives.....and six seats away from "losing the senate."
"I want you to think for a minute what could happen if we lose those seats,'' she said.
She said Americans could see votes that "interfere" with women's contraception or with laws that allow Americans to marry "the one they love."
"This year, we have 36 governor's seats up for grabs,'' so "it is simply not enough to elect Barack Obama president."
"Starting right now, today, we need to be as passionate and as hungry that we were in 2008 and 2012 -- you hear me?
'We need to be even more passionate and more hungry because these races will be even harder,'' she said.
"One of the reasons these midterm races are so tight is because too often, we don't show up -- you hear me?" she said, noting a "significant drop off in young people, women and minorities.
"It's on us,'' she said. "We can't just sit back and hope for the best..and be surprised and outraged when things don't work out."
"We do that well, she said.
"You can write a check. Or another one. Write a big fat check. Write the biggest check you could possibly write."
"Some of you might be tired being always asked for money,'' she said. But "I know that writing those checks is the single most impactful thing you can do right now" to affect the outcome of the 2014 elections.
"It's not enough to have the best values and ideas if you never get the chance to make them into laws and policies,'' she said. "it's not enough..to wait for things to turn out OK."
"We need to act. And when we turn our actions into dollars...it translates into calls made, doors knocked on."
"We need you to dig deep. We need you to max out right now,'' she said. "We need you to volunteer...especially in safe states like California, we need you guys to go someplace else."
That "means the difference between victory and defeat."
"So many people are counting on all of us,'' she said.
"Because no one in this country should work 40 or 50 hours a week and still be stuck in poverty...that's not who we are.''
"If we all keep stepping up and digging deep...we can keep moving this country forward, and together, we will build a future worthy of our children,'' she said.
Financial district streets were lined with onlookers as she left the One Leidesdorff building on Pine. No incidents.