Kasich has affluent suburban appeal....just saying. Kasich is beloved in St. Charles, MO, Miami Dade, and Morris County in NJ...just saying. Kasich could be a third party threat.
A 3rd party threat to who? I don't see anyone who voted for Trump in 2016 voting for Kasich in 2020.
It would definitely be more likely his supporters - like the Bush family & followers - voted for Hillary or stayed home in 2016. Kasich could only take Hillary's voters if she ran.