Were this a secret vote, he'd be convicted. But the identity and sense of self-worth of these GOP senators is absolutely tied to their status as, well,  senators.  If they vote to convict, Trump will be relentless in demonizing them, rabid dog that he is, and they will probably be ousted by the cult. They know that once they are voted out of office, no one will give a shit about their opinion. The Sunday talk shows won't seek them out. The chattering class dinner invitations will cease, and they'll be cut loose to eke out a living as lobbyists. 

Peter T.