Can these “R”s be summarily expelled from the party now? One hopes...
Find primary opponents to beat them ! That expells them !
There’s no way to keep someone from calling themselves or registering as a Republican. Ameican political parties aren’t like the old Soviet Communist party they can’t control people to that level yet ! Remember David Dukes registered as a “Republican” and I think won a seat in the Lousiana legislature. Hypocritical yes but I doubt if Dukes worried much abut it.