Actually, yes. To start with, some of the most onerous, entrenched and repulsive Republicans have been kicked out of high office. Far more, at state level, have been replaced by conservatives.
Granted in this last election, “The Empire Struck Back”, in keeping seats, taking back control of some state parties, and inserting faux conservatives into office. But it was very expensive to do what amounts to a defensive action.
And, as Napoleon observed, a static defense is slow suicide.
Comparatively speaking, Mitt Romney had a far easier time to the nomination than is Jeb Bush; and it was a waltz for McCain before him. Eventually, perhaps with this next presidential election, it is going to break the bank of the big money backers. They’ll have to do it on their own because there will not be any grass roots money flowing to their people.
So yes, the more the Republican liberals are eroded, the less they are able to fight the erosion, until that happy day when conservatives fully take control of the party.