Cries of racism have done little to sway Mississippi's largely white, Republican voter base.
Republicans are losing solidly red districts, and their tax plan isn't helping.
White people almost single-handedly elected a homophobic, anti-Muslim accused child molester to the Alabama Senate.
The alleged voter suppression has disproportionately involved people of color, according to rights groups.
Polls close at 7 p.m. EDT.
The runoff for the House seat is set for June 20 in Georgia's 6th congressional district.
Gianforte was charged with misdemeanor assault after allegedly body-slamming Guardian reporter Ben Jacobs.