They are finished if they try to convict Trump.
I don’t think that’s the plan. The GOP Senate will mostly “support” POTUS by NOT convicting him. Short term they want to keep Trump on a leash inside the party and endorsing GOP candidates. Trump taking much of the GOP base and going third party would destroy the GOP. They know that.
Trump is so far out of the party and has been from the beginning that you’re not understanding how this works…
I hope you are correct.