I would suggest that sin is sin regardless of what sin it is. Just because some sins are not called out does not mean they they are not sin. Of course they are. The decision to vote or not vote is one between an individual and God. Personally, I believe it is important to use a gift that God has given us. And He has given us the gift of being able to choose our leaders. Surely He expects us to use that gift, and to use it to promote His world view.
Therefore, in a situation where one leader vows to continue to confuse children (and adults) about gender, to enable their sexualization, to usurp parental rights, to expand the killing of babies, to restrict free speech, and to put limits on Christian beliefs, while the other leader vows to protect those things, then as a Christian how can I not make my voice heard? How can I not vote for God's values?
Yes, this is a secular society; but that is exactly where God has placed us. And He placed us here to be salt and light. Salt does no good if it's kept in a box. Light does no good if it remains covered. We need to go out and make sure we do all we can to promote what God wants, which is by the power and leading of the Holy Spirit to restrain evil during this Age. It is our responsibility as part of His Church. A responsibility for which we will answer one day. And, in this country, voting is one of the tools God has given us to accomplish His will.