Michelle Obama is exhorting grass roots supporters to keep working hard for her husband's re-election.
The first lady rallied hundreds of people on Thursday at the University of the Sciences in Philadelphia, the first of three stops in the state. She says President Barack Obama has fought to keep the American dream alive for the middle class.
She later plans to attend campaign events in suburban Fort Washington and farther north in Bethlehem.
Pennsylvania voted for Obama in 2008. However, the state has a strict new voter identification law that critics say will disenfranchise likely Democratic supporters in November.
The law is being challenged in state court.
