The following refresher from Pope Pius XII touches on the importance of Catholics voting...
"Consequently, there is a heavy responsibility on everyone, man or woman, who has the right to vote, especially when the interests of religion are at stake; abstention in this case is in itself, it should be thoroughly understood, a grave and a fatal sin of omission. On the contrary, to exercise, and exercise well, one's right to vote is to work effectively for the true good of the people, as loyal defenders of the cause of God and of the Church." (Pope Pius XII)
Commentary: It should go without saying that Catholics must vote like good and faithful Catholics or else they may do more harm than good.
"[A]ll those are pitiably deluded, whose theory of government makes no account of man's last and highest end, of the right use of the goods of this life." (Pope Pius XI, "Ad Salutem", 1930)
"[S]ince men united by the bonds of a common society depend on God no less than individuals, associations whether political or private cannot, without crime, behave as if God did not exist, nor put away religion as something foreign to them, nor dispense themselves from obtaining, in that religion, the rules according to which God has declared that He wills to be honored. Consequently, the heads of the State are bound, as such, to keep holy the name of God, make it one of their principal duties to protect religion by the authority of the laws, and not command or ordain anything contrary to its integrity." (Pope Leo XIII)
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