Trump dominates the GOP because people who never voted before registered and started voting when he was on the ballot. Many are not that issue-oriented. They (often rightly) feel fucked over, and are looking for a brawler to stick up for them.
Clearly lots of MAGAts think "reverse discrimination" is a big part of how they get fucked over. Sharpton may be the one to show then you need to unite with, not blame, the other people who are getting fucked over: news.yahoo.com

