Many would tell us, “A vote less for X is a vote more for Y”, yet Glenn Beck basically made a great rebuttal and in paraphrase, “If a vote less for X is a vote more Y, then does that mean a vote less for Y is a vote more for X.” I’m not a Beck fan for a number of reasons, but this was very clever. We are constantly told that those who don’t vote contribute to the outcome of the election in favor of the greater of two evils. Yet for the reason mentioned above, this is illogical. Things keep going on: if I refuse to vote because I view X and Y as about morally corrupt as each other, then I do not contribute to either one’s victory or loss. For one, neither candidate owns my vote. They have to earn my vote and if they don’t then they do not deserve my vote.
So, this leads me to Catholic doctrine on voting. Let’s keep in mind for the majority of Christian history; most Christians were not allowed to vote as voting was restricted to nobility. In the Holy Roman Empire for example, peasants could not vote and the emperor was elected by prince-elects. Other times emperors and kings were either brought to power either by inheriting the throne or by winning a war against another rival as in the case of Augustus Caesar against Mark Antony. In such cases a Christian who had no ability to vote obviously could not have sinned. In other instances Christians were forbidden from voting because of their religion.
So, what about those cases in which Christians can vote? Voting is encouraged wherever and whenever possible. This is because Christians have a duty to bring up about the greater good in society. Therefore Christians should vote with a good conscience; but if there is no good option, Christians can opt out of voting as many did throughout history, if the individual sees the evils of the candidates are too grave. This brings me back to my post about Adolf Hitler and Josef Stalin. Venerable Pius XII spoke on this.
“[I]t is obvious that the voice of conscience imposes on every Catholic to give his vote to the candidates who offer truly sufficient guarantees for the protection of the rights of God and of souls, for the true good of individuals, families and of society, according to the love of God and Catholic moral teaching.”
So while he said who “abstains from doing so, … commits a grave sin” that is only so far as there are “candidates who offer truly sufficient guarantees for the protection of the rights of God and of souls, for the true good of individuals, families and of society, according to the love of God and Catholic moral teaching.” Otherwise, one is not morally obliged to vote; one cannot consciously vote for one he/she sees as too insufficient which is why the Church does not lay any burden on us.
You can read more here: http://archives.sspx.org/miscellaneous/catholic_principles_for_voting.htm