This claim is made over and over by Republicans who simply don't want to accept the fact that while Pennsylvania is a conservative state, it is also a Democrat state. I used to believe it myself, but it is simply not true. There are plenty of irregularities in Philadelphia, but believe me, the Philly Republicans watch the precincts very very carefully.
Republicans will continue to lose in PA until they get their message to the Philly suburbs and to ethnic Roman Catholics in coal country. Everyone knows we lose Philly, heavily. We make up for that in the rest of the state, but in the last two elections we simply have been clobbered by the five counties surrounding the city. Time to stop blaming fraud, learn from our mistakes and get the message to the suburbs.
My point was and is that there were plenty of irregularities on the demoncrat side, and they were more serious than exit polling that nobody uses because it's not accurate. Look no further than 2000 when the alphabet networks learned that lesson.