Y'know, if Trump were actually smart, he would take advantage of this situation this way:
1.  Fire Bannon and that Gorka creature who's been talking from the WH;
2.  During the "announcement press conference", say the following:  "I tried listening to Bannon and his people.  The more I learned, and the more I've seen, I realize how disgusting and dangerous they are.  I was in bed with them.  I've gotten out of the bed.  It stinks."
3.  Openly direct the AG to pursue investigations of not only the Charlottesville incident, but the general activities of all identifiable White Supremacy groups.
4.  Speak out against any rallies by White Supremacy groups, and order an FBI presence at each.

Trump could actually romance the left by doing this. 

The left would accept out of a desire and sense of relief.

It's a no loss proposition for him.  Sticking with the White Supremacist movement is a loser.  A YUGE LOSER!