Power is always a fluid concept and susceptible to change. They would hold that power but for how long? The right understands that Trump, despite his flaws and self-serving nature, has done more to consolidate right wing political power than any politician on any side has in any living persons memory. They are gleeful to serve him, and get a thrill from cheerleading his insanity. Thats not to say that there arent a few greedy dumbasses in the party who might fool themselves into thinking they could successfully usurp Trump, but I doubt theyd succeed, or get very far after they did. Vance would fall apart like wet shitty toilet paper soon after.