Funny!
I would think that being a Trump supporter is inherently an insult!
I had someone call me a "trumpet" on a particular FB forum - which was usually a civil one - because I told someone that their calling Trump "Donald Hitler" was inappropriate for that site and didn't do anything to advance their argument. I got jumped on as a "trump supporter" just because I called for civility. I "unliked" that site...
Anyway, that's why I used Trumpet. But Trumpeteer works.