If Rudy wins the primaries, the November election will be liberal v. liberal and conservatism will have already lost.
It's not about party, it's about politics. I am a Republican when they are conservative, and not when they are not. I've never knowingly voted for a pro-abortion gungrabbing liberal and I'm not about to start now.
If the GOP nominates a pro-abortion gungrabbing liberal like Rudy, they forfeit my vote, and the consequences will be their fault not mine.
There are many like me. Enough to cost a few states.