If Wolf is unpopular enough, he very likely won't even run again. If he's anywhere near Corbett levels, he definitely won't run again. I'm already very much a believer that Casey has a strong chance at being the nominee in 2018.
His seat is too precious. Too risky
The PA Dems don't have a bad bench. They could easily find someone to replace Casey.
Such as Schwartz?
She'd want to but she'd probably be too old by 2018.
Congressman-elect Boyle would surely run whenever there's an open seat. 2018 would almost be perfect for him.
Who do you think would be the strongest Republican Senate nominee for Pennsylvania in 2018?
We're still too far out to say. Luckily, we have a bench.
And so do the Democrats, thankfully.