Just as PA has many switching from dem to rep, there are also many who will stay with their Party but jump to trump this cycle to keep their Party from being destroyed. I know a number of long-term hard-core lefties who will stay with their Party but will vote trump to keep the disaster of Hillary out of the WH.
Rust Belt in general has a far bigger story going on than anyone is willing to admit to... the Trumpocrats are real, they are large in number and they aren’t just going to Trump because its Trump....
The rustbelt is seeing the effects of democratic policies as their towns are being decimated and that the party doesn’t represent them... blue collar whites are starting a well overdue realignment this cycle... Trump finally dumped the “free” trade dogma crap that has helped keep the rust belt mostly D.... IF republicans are not stupid, the entire rust belt could realign as working class whites there abandon the Dems... just like they did in the south in the 60s and 70s, and the result could literally be the rust belt being as reliably republican as the south within a few cycles...
But, this will only happen if Republicans aren’t stupid.... and that’s a big big if.