FWIW, I have a very good friend who is very active in the League of Women Voters (non-partisan group) in the Detroit area. They have been active (poll/count) observers during recent elections and they are watching this sort of stuff closely. They helped get the district reform initiative on the ballot (later axed by Snyder and the state GQP after it won with 60% of the electorate).
While they sort of fly under the radar, they can make a difference. Any Michigan TPM ladies who aren’t involved might want to consider. They do good work.