I'm looking at the election odds for a Trump/Hillary matchup and the odds are about 25-30% Trump wins. I don't see him winning without winning PA or VA. How exactly will Trump win PA? "He won't" is not an acceptable answer.
You don't win by being positive, you win by being negative. Successful Presidential candidates have known this for at least fifty, and possibly for over two hundred, years. To win PA Trump will have to go hard on Clinton, and better yet link her to Governor Wolf, who currently has a 33% approval rating according to an F&M poll from January, or 41% according to Quinnipiac. Either way, he's getting blamed (probably unfairly) for a number of the state's problems, including the budget impasse. All Pennsylvanians are aware of this problem, although whom they blame varies. Clinton, of course, has nothing to do with this problem, but she is a Democrat like Wolf, along with Pennsylvania Attorney General Kathleen Kane, who was charged with perjury, saw her law license suspended and now is facing possible impeachment proceedings in the House. What Trump wants to do is attempt a strategy of assigning guilt by association. Among casual voters, this could work.
Also, support for medical marijuana has increased dramatically in Pennsylvania of late. One poll showed 90% support in PA. I don't see Clinton going there, and she has been very reluctant to endorse the program, saying that the "jury is still out" on whether it has any benefit. Trump could trot it out big. He has recently given his unequivocal support for medical marijuana. In February he said to O'Reilly that "I know people that have serious problems and it really, really does help them."
Of course it's a long shot, but that's how I'd advise Trump regarding Pennsylvania.