Yes -- the ill-fated Bull Moose Party. Teddy and Richard Nixon are the two biggest Republican disappointments of the twentieth century. They ran as arch-conservatives and governed as liberals.
They had the chance to restore much of the Founders' vision and they wimped out. Especially G.W. with support in Congress available to him. Shame he lost his veto pen and tried to "make nice" with treasonous Kennedy. Sigh.