There are many Republican electors who would not vote for HRC if Trump actually got on a live broadcast and shot someone dead in the middle of the street.
They don’t have to.
All they need to do is vote for a real Republican. Any Republican. Cruze. Romney. Fiorina. Bush. (Jeb or even G. H. W. Not W, though.) Collins. Flake. Powell. Kim Kardashian. Pick one. Pick one and vote not-Trump.
Pick enough that the tally for Trump drops below 270, and it gets thrown to the House.
Yes, that means a Republican will be the next president. But it will be a Republican with some sense of civil responsibility.