Things that would otherwise destroy any other party:

1) incessant race-baiting;
2) threatening political opponents with assassination;
3) hiring campaign manager with ties to foreign govts and mysterious payments for same;
4) no transparency on his personal taxes, bankruptcies, and how his income is generated - refusing to release tax returns;
5) running a fact-free campaign where candidate can’t even keep his story straight in a single conversation;
6) cozying up to former media executive who was booted from media organzation for sexual harassment of multiple women;
7) etc.

These same things are the very kinds of things that endear himself to the core GOP voters. That’s why Trump is continuing to do what he’s been doing.