No matter how powerful or how democratic the government might be, if they should declare something to be a right which is not in accord with the truth of man expressed in the natural law, such a right would not be a law but a usurpation of law.
Voting then must be guided by the truth. It is possible that a person would vote for a given imperfect candidate because even though they found some of their ideas about individual laws repugnant they recognize that a vote for such a candidate minimizes the evil that can be done when compared to an even more problematic candidate whose policies are worse.
For instance, this would be the case with a candidate whose policies would allow for abortion in the case of rape or incest versus someone who supports abortion on demand. This would presume that there was no electable candidate who opposed abortion in all cases. Even though both candidates approve abortion, one would save many babies. Their error has no right to exist but it would be a worse evil to elect the other candidate. Evil is tolerated here because of the possibility of a worse evil and the impossibility of completely establishing good.
Without the prior existing nature as the source for both rights and conscience all morals become relative and then only the most powerful determines even the right to life, who lives and who dies. The most powerful would then play God. It is only when statesman and voters do not forsake their private conscience for the sake of their public duty that any country can be saved from moral chaos.
Full article . . . Politics for All Seasons – Truth and Charity Forum.