Which is not entirely fair, speaking as an ex-evangelical. Plenty of fully dedicated evangelicals disapprove of Trump. And while a disappointing number of them do approve, it's by no means a unified base.
I've met both kinds of Evangelicals. I think we need to figure out a term to differentiate between the normal Evangelicals and this strange subset of American Evangelicalism.
Support for Trump among Evangelicals has always remained steady at or slightly above 80%. The "strange subset" of Evangelicals are the ones who don't support him, the "normal" ones are the ones who do, by a wide margin.