"Christians are sanctified by faith and the sacraments of Christ, according to 1 Corinthians 6:11, "But you are washed, but you are sanctified." Wherefore it is written (1 Peter 2:9): "You are a chosen generation, a kingly priesthood, a holy nation, a purchased people." Therefore any injury inflicted on the Christian people, for instance that unbelievers should be put in authority over it, is an irreverence for a sacred thing, and is reasonably called a sacrilege."  S.T. II-II, Q. 99, A. 1, Ad. 2.

All this talk of whose the best, most conservative, most constitutional "candidate" for political office fails to take note of this essential truth explained by St. Thomas.  We have fallen so far from the exemplary forms of Christendom that no one today even considers what being under the "yoke" of unbelievers means (conservative though they may be) and the continual infliction of injury upon Catholics.  So entrenched has this rule of unbelievers become over Catholics, that Catholics themselves have utterly lost their identity.    

And regarding so-called "conservatives" today, they conserve nothing but classical liberalism.  No catholic can stand side by side with them on a theoretical level because an apparent agreement harbors the most pernicious of errors.