I like how we do it in Australia, our Christian faith and politics (for the most part) don't mix.
We do not disagree on much, but I think I will have to question this concept. Now, this is just my opinion, so don't take it for Biblical Truth.
To me, being a disciple of Christ is not a part-time calling. It is a way of life. I'm thinking of one Scripture in particular:
Colossians 3:17) And whatsoever ye do in word or deed, do all in the name of the Lord Jesus, giving thanks to God and the Father by him.
And this is echoed in 1 Corinthians 10:31) Whether therefore ye eat, or drink, or whatsoever ye do, do all to the glory of God.
I am led to believe that whatever I do, I must try to do for the Glory of God, and this includes how I view social/political issues, how I vote, which Candidate/Party I support. If I set aside my Christian Faith when I step into the voting booth, I don't see how a vote cast could be for the Glory of God.
Anyway, just my thoughts as to why I feel the way I do about this. God bless