Clinton will start Monday in Pittsburgh before making stops in Montgomery County and Philadelphia. He'll end the trip with a rally in Scranton, the hometown of Vice President Joe Biden, U.S. Sen. Bob Casey and Democratic attorney general nominee Kathleen Kane.
Obama, Casey and Kane are leading independent polls in Pennsylvania.
But Republican presidential nominee Mitt Romney and conservative groups are making a big, 11th-hour push in a state with the fifth-most electoral votes. Pennsylvania has supported Democrats in presidential elections since 1988.