PA did well in 2010. GOP governor and U.S. senator and turned six congressional seats from blue to red. An excellent showing for what is supposed to be a blue state.
If GOP turnout in PA rivals that of 2010, Romney could very well win.
If this ends up being more like 2010, I'm hoping that Romney has long enough coattails to deliver the Senate race for Smith (over Casey) and the PA-12 House race for Rothfus (over Murtha's successor Critz).
In 2010 Westmoreland County (parts of which are in PA-12) went Republican across the board, including for the two County Commissioner seats - something that hasn't happened in recent memory.