Christians must be involved in politics and vote for the most godly candidate.

Politics tend to rile people up, and Christians aren’t exempt from the emotionalism involved. I’ve heard preachers say, “Anyone who don’t vote ain’t a Christian!” They forget that the Christian’s “citizenship is in heaven.” (Phil 3:20) The bible nowhere calls for Christians to become concerned with trying to make this world better. As long as godless men rule the world it doesn’t make a difference who is in office, what party it is, or even the ideology. Men have absolutely ruined entire nations, whether they were democrats, republicans, or communists.

During Paul's time, Rome was in serious trouble, financially, politically, socially, and morally. One need only do a casual reading of some of Edward Gibbons' Decline and Fall of the Roman Empire to get an idea of the problems that existed. Yet none of it is even mentioned in the New Testament. There is no call by the apostles for Christians to get out and vote or march in protests. None of it.

Christians should strive to set examples for the world by their Christ-like behavior. Once the gospel regenerates individual sinners, then the world can become a better place. It’s not going to become one simply by voting for who we think is the better candidate. It’s a person’s right and privilege to vote, and we should strive to support the principles we believe in. But claiming that our salvation is in jeopardy if we don’t vote is rank extremism. If you're going to put politics as part of God's salvation plan, you're inviting His curse. (Gal. 1:8, 9)

Jesus never involved Himself in politics, nor did He try and persuade His followers to do so. He said that His kingdom was not of this world. (John 18:36) Paul told Christians to live within the laws of the land. (Rom 13:1) Christians are to “pray for kings and all who are in authority, so that we may lead a tranquil and quiet life in all godliness and dignity.” (1 Tim 2:2) He said that this was God’s desire, but not in order to make the world a better place, but provide an environment where people could receive salvation. (1 Tim 2:3, 4)

In the famous faith chapter of Hebrews 11, the writer speaks of many God-fearing people who shunned this world, preferring the world to come. None sought to make it better by marching, waving banners, and shouting for reform.
If you feel strongly about certain issues, go for it; just don't try and add it as a prerequisite for salvation.