He has one gigantic problem however, one which is just as damaging as the heavily-Democrat makeup of the district, and that problem is illustrated here:
FEC financial reports for PA District 12
As things stand now, he's lucky to be able to afford a few yard signs. In a district like this which isn't even considered to be slightly marginal, the national GOP with its limited funds isn't likely to make anything more than the smallest token effort on his behalf.
Now if Lee wins the primary today AND if subsequent polls quickly start showing that she's weaker than expected for November, that might be a different story. It's still quite a long shot.