He argued that he has strong momentum in the state and that, "the only way we can lose, in my opinion, I really mean this, Pennsylvania, is if cheating goes on."
Trump said: "We're going to watch Pennsylvania. Go down to certain areas and watch and study make sure other people don't come in and vote five times."
(Not the central issue, but every four years Republicans and the media make a big deal about how PA is a critical swing state which could go Republican, and then it doesn't. Sure Republicans can win PA, but it'd be a national landslide if they do so PA wouldn't matter much. I's a reliable, if fairly close, Democratic state in presidential elections...)
The good news is those people are deathly afraid of Philly. The bad news is it only takes one nutcase with a gun.
It'd be pretty hard to pull off that kind of voter fraud in Philly. Sure other kinds of fraud would be possible, but the "people voting multiple times" type is really the stupidest possible way to try to get some extra votes.
...in case you didn't read to the end:
"The people in western and central Pennsylvania have to overcome what goes on down in Philadelphia," said Shuster. "The cheating, what they do -- we've got to make sure we're doing the job here in central Pennsylvania."
It's how the rest of the state (even Pittsburgh, to some degree) see Philadelphia. It'd be funny if they didn't control the state legislature and many public agencies in Philly (the state regularly makes special rules for Philly because the city can't be trusted to govern itself, as is regularly proven by the horrible state-run agencies that run parts of the government...)