I can see how independents who lean Rockefeller Republican were also for Clinton in 2016, Trump was too foreign and espoused views that conflicted with their morals. I imagine most of them voted in the Republican primaries for Kasich, but supporting Clinton after Trump won the Republican nomination.
There are LOTS of these in suburban Southern California.
I'm in Middle Tennessee, although I wouldn't consider myself a Rockefeller Republican, I voted for Rubio in the primary (my whole family actually voted strategically, trying to draw delegates away from Trump we decided my mom and I would vote for Rubio to boost his numbers by 2 because he had less strong support in TN than Trump or Cruz, and my dad would vote for Cruz because he had stronger support than Rubio but less strong than Trump) and after Trump clinched the Republican nomination, my mother and I were going to vote for Gary Johnson, then when McMullin entered we supported him. My father moved towards supporting Trump. We're all neocons but it was basically me and my mother were like "if not having Trump president means Clinton being elected, then so be it" while my father was like "Republican no matter what"