WAYNE, Pa. — Mitt Romney declared Pennsylvania a battleground during a mid-morning rally here Friday, despite public polls showing him well behind in the race for the state’s prized 20 electoral votes. “I’ve got a little secret here and that is that the Obama campaign thinks that Pennsylvania is in their pocket. They don’t need to worry about it,” Romney said during a visit to a military academy in the Philadelphia suburbs. “And you’re right and they’re wrong. We’re going to win Pennsylvania and we’re going to take the White House.”