I've been living in PA for about 9 years, and there's a certainly been a shift. While Philly is, and will remain, Democrat, there is much more Republican support in the suburbs. You see far more Romney stickers and signs than you did signs for McCain in the last election. Even around my alma mater, people who may have kept quiet four years ago are now comfortable voicing their opinions. One former classmate of mine has changed from being an Obama volunteer to a Romney fundraiser. There's no guarentee of victory, but it's going to be a much closer race than PA usually sees.