So far there isn't a viable candidate on the GOP side running against him that has a snowball's chance of winning.
Only because the cult of partisan politics, the same cancer that Trump's supporters were supposed to be against, makes it impossible for any person to run against an incumbent in his own party, no matter how much that challenge is needed.
When was the last time an incumbent saw a real challenge? 1980 with Ted Kennedy? When was the last time an incumbent was ousted in a primary? Ever? I vaguely recall maybe the 1850s, but it's been a ridiculously long time.
It's disgusting. Three years ago we were all warning y'all about Trump and his narcissistic, erratic behavior... but now that he's the incumbent, we have an unhinged liberal Republican waiting to go total fascist once he's a lame duck, against flat-out socialists. A no-win scenario. And the conservatives like Walsh and Amash, who we once cheered as the conscience of the party, are now
persona non grata when that conscience calls out Trump's liberalism.
"No one can win," they tell us.
Well, that's YOUR FAULT for blindly supporting bad incumbents! If we're going to follow Duverger's Law and maintain the two-party system, we have to make sure that we actually have good choices. 2016 left us with two horrible choices. Let's not make that mistake again!