If you go with the theory that the GOP [national] (1) has an elitists leadership, and (2) is far more corrupt/complacent/complicit with the various improprieties around, then it clarifies things a lot.
It's not cheerful, but that's the second simplest explanation as to why the GOP doesn't have conservatives winning their primary.
(The dead simplest is that the voting-base in the primaries isn't conservative.)
It not a theory. It is as plane as the nose on your face. The GOP is full of the children of the Global elite and so is the DEMS.