1) Get the words right.
I’m reading a story, and one character says he’s active in the Minnesota Democrat Party. Unless this is alternate history, I would find something else to read. To begin with, “Democrat Party” started as a Republican dysphemism for the Democratic Party. A Democrat might use it; but the more active in the party, the less likely.
And it’s vanishingly unlikely that he’d say “Minnesota Democratic Party,” either. In Minnesota, it’s the DFL. (There was a merger between the Democratic and Farmer-Labor parties in 1944. I can’t detect any trace of the latter in today’s party, but the name does remain.)
Thanks to the proliferation of political blogs, you can get a reasonable idea of which words members of a political movement use. Be aware that there are almost certainly splits within any movement with more than five members, and these may be reflected in their words.