“Saddest of all is the GOP Senate may very well continue to protect him and stonewall his removal, believing that they are electorally invulnerable in 2020 and 2022.  That’s the only firewall to get him, or Pence, limping into 2020 still in the WH.  But that firewall would doom their control of the Senate.  Like every tragic character felled by overconfidence, they never see that their invulnerability is overrated until its too late. We’ve always been able to count on Republican arrogance leading them to shooting their damn feet off, eventually.  This group of political morons is several generations more deluded by the Fox News base than the group of statesmen (read: realists) that forced Nixon out.”

I would only add one thing:  I think they know that they’re vulnerable in 2020. I think they’ve calculated that it’s more important to be a member in good standing in the Trumpist party even if an ex-Senator. Being a Trumpist ex-Senator is way safer than being an apostate Senator.