It won’t work that way. There will be enough democrats and rinos to push any nominee through. Without 60% control by conservatives, moderate/libertarian/unknown nominees will get through.
There is no way they will achieve 60% conservative senators, since they’re supporting all of the retreads with the exception of Lugar and maybe Hatch.
We only need 41 for a filibuster. I think that after seeing folks like Bennett, Lugar, MurCOWSkee, and possibly Hatch be defeated in GOP primaries, even some of the RINOs may feel the need to pressure Mitt into appointing real conservative judges