I feel most Republicans will be standing by him. A lot of confressmen are condemning him because they're afraid of angering the Democrats. Most Republicans feel that the media whitewashing Antifa is worse than Trump not "specifically" calling out white supremacists. A lot of Democrats say that their side of the story is legitimized by what they stand for and the fact that the only death in the rally was one of them.
It's not those types (which are gonna hold out to the bitter end), it's the Indies, Moderates, Not-so-Ideological types that are critical to keep hold of.
They are the ones who ensured Trump would have barely over 50% after he just won (and the ones who held their nose just because he was new and Hillary wasn't), they are the ones who have ensured he'd be at 44% by inauguration, and they are the ones who got his numbers down to where they are now.
Congresscritters aren't condemning him for the sake of appeasing Democrats, they're doing it to appear reasonable to those not so entrenched.