I don't think that's true. I think many of those 40.4% are caught between a rock and a hard place. Their star pitcher is fumbling the ball and throwing wide, the bases are filling up and it looks like they will lose the game. But they still have to support the team.
Most republicans didn't like Trump, but anything was better than that bitch Hillary. The president doesn't have that much power anyway, so how bad could it be? Now they know.
Trump has them by the balls now. If they don't approve then they aren't real republicans. If they do then they will be accused of being racist, sexist, and Nazi sympathizers. They know they aren't, but what can they do? The alternative is unthinkable - so they grit their teeth, put on a happy face and tick 'approve'.