PHILADELPHIA (AP) — Michelle Obama exhorted grassroots supporters on Thursday to keep working hard for her husband’s re-election, saying the president has fought to keep the American dream alive for the middle class.

The first lady rallied more than 1,000 people at the University of the Sciences in Philadelphia, the first of three stops in the battleground state. She stressed the campaign’s “It Takes One” initiative, which asks each supporter to inspire one more person to help President Barack Obama win another term.

“That could be the one that makes the difference in this election,” Michelle Obama said.

Pennsylvania voted for Barack Obama in 2008. The state has a strict new voter identification law, however, that critics say will disenfranchise likely Democratic supporters in November.

The law is being challenged in state court, and a judge is expected to rule this month. Michelle Obama did not refer to the law in her remarks.

She listed the accomplishments of the president’s first term, including the health care overhaul, auto bailout and winding down the war in Iraq. Obama also noted the president signed bills preventing student loan interest rates from doubling and providing more money for Pell grants for low-income college students.

Both she and the president had mountains of student debt, Obama said, adding that at one point their monthly student loan payments totaled more than their mortgage payment.

Her 30-minute speech also touched on the couple’s humble backgrounds, saying they both come from families that worked hard and valued education.

“Barack knows the American dream because he’s lived it,” she said.

Earlier this month, a Quinnipiac University poll of likely voters in three key battleground states found the president leading presumptive Republican nominee Mitt Romney by 11 percentage points in Pennsylvania.

Supporter Hope Fleming, an elementary school teacher, said after the rally that she was struck most by Obama’s stories about her father, a longtime municipal employee who worked hard to move their family forward.

“I felt like she knew me, and I knew her,” Fleming said.

Later Thursday, Obama spoke to 1,800 supporters at a high school in suburban Fort Washington before heading north to rally supporters at Moravian College in Bethlehem.

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