Well, I'm thinking they could both be replaced with absolute crackpots, due to who they represent.
To me, it just speaks more than ever that the DNC needs to work exceptionally hard to make Manchin irrelevant this mid-term; get enough seats in the majority (3 more?) and they won't have to make him the linchpin that he's become today.
I think if the Dems keep it 50-50 it will be a hell of an effort. Three seats GOP has a good shot at and only a couple the Dems realistically could flip. One thing they should do is empower local officials and don’t dictate too much from Washington.