I wish I could take credit for this but it's an interesting comment to an Washington Post "Plum Line" article by a user called AlexOldTown.
Trump has done something interesting actually. By distilling out the racism and xenophobia of the GOP to a much higher proof, he's actually stripped out much of the plutocrat agenda. The racists, along with the evangelicals, are how the GOP has gathered up enough votes to enact its agenda for the rich. And that continued use is part of the reason the base is so mad. But he's demonstrated that much of the base, the haters at least, are not at all interested in the plutocrat agenda. (I'm not so sure where the churchy types are on Trump.) Now that they can get their hate at a much higher proof they are dumping the rich guys.