Probably the NT Scripture most directly applicable to politics is RM 13:1-7:
Everyone must submit himself to the governing authorities, for... the authorities that exist have been established by God. Thus, he who rebels against the authority is rebelling against what God has instituted... For rulers hold no terror for those who do right, but for those who do wrong... He is God's servant to do you good, but if you do wrong, be afraid, for he does not bear the sword for nothing. He is God's servant, an agent of wrath to bring punishment on the wrongdoer. Therefore it is necessary to submit to the authorities, not only because of possible punishment but also because of conscience.
This is also why you pay taxes, for the authorities are God's servants, who give their full time to governing. Give everyone what you owe him: If you owe taxes, pay taxes.
This passage should be interpreted along with Acts 5:17-30, in which the Sadducees arrested the apostles and brought them before the Sanhedrin, and the high priest gave them strict orders not to teach in the name of Jesus, but Peter replied, "We must obey God rather than men!"
Sewing these two passages together, we understand that authority established by God does NOT contradict the Gospel that "Jesus is the Christ" (Acts 5:42) and Christ's law of love.