There are a lot of very intelligent Trump supporters.
Those people on the film from the New Yorker reporter, that had the guys in the Senate chambers? Those people were morons.
I don't mean they were saying things I didn't agree with. I don't mean that they were saying things that I think were unsupported, or even stupid. No, I mean they, themselves, at least the ones that were talking, were dumb as posts.
ETA: I assure you that I have expressed exactly the same sentiments that you have, and in fact more strongly. Not only do I not think all of Trump's supporters are stupid, I also don't think all of Trump's positions are stupid. I can understand why people would pull the Trump lever* even if they are extremely intelligent people.
Those guys in the Senate chamber were just plain idiots.
*I suppose that's just a metaphor these days. I don't think any voting machines currently in use have levers.