I have a question and I haven't prayed on this yet but I wanted to get feedback:
I have been a libertarian for many years. That's an ambiguous term so let me define: I believe we all have free will and the right to exercise our wills within reason (ie - you can't kill someone if you disagree etc). I have not necessarily supported abortion, gay marriage, drug abuse etc but I have maintained that it isn't my place to place edicts on other people who choose those things.
As I have recently looked at my own faith and realized my own shortcomings as well my decision to run from God, I have decided to accept God's will in my life and recommit to Him. While I have a multitude of issues on my plate, I have begun to consider my political identity and it's relation to my faith. Perhaps in time, God will move me to reexamine and maybe that time is now.
As I look at everything I fundamentally believe about how freedoms and rights are paramount to govt sanctioned and enforced morality, I wonder if I am putting my own beliefs ahead of what Jesus taught us and the scriptures say. Is it possible to be a Christian and support a woman's right to choose even if I disagree with the choice? Is it possible to accept people's right to marry or have a civil union or use drugs or hire prostitutes and be a Christian or are we charged to use a govt to enforce our beliefs?
I realize that I have used some charged words like "enforce" and I am not trying to ignite a wild debate over the politics of a country, I am simply wondering if certain libertarian political values I hold are in line with what we are charged as Christians to uphold?
Interestingly, Jesus' commandant: "Give unto Caesar what is Caesar's and give unto God what is God's" has been used as one of the most powerful testament to secular governance.
Now, at the risk of sparking controversy I want to address some of your concerns--what you are tempted to support politically.
Abortion in particular I think is something that a Christian cannot support without reservations (i.e. rape, incest and when mother's life is in danger). This is more do to an ethical concern, however, than purely a Christian one. The whole notion of abortion is highly problematic for anyone attempting to maintain the sanctity of life. And I have heard of people supporting infanticide--most pro-choice don't support that, but in all honesty I don't understand why that is so much more abhorrent than partial birth abortion. There was also recently a woman who filmed her pregnancy and abortion as though it were as "special" as giving birth. These are things I find very disturbing even as a humanist. Unfortunately, I think this issue is "the" most decisive of our lifetime because it pits people at odds between sanctity of life with fundamental human rights (namely, privacy). I consider the argument, however, to have serious parallels with those who argued for slavery. So as a matter of principle, supporting abortion is problematic for Christian faith, just as slavery was. But, you are under no obligation to pass judgment on a person who has had an abortion. Also, fortunately, abortion is not really a political issue for those living in the USA, because as the law stands, there are only two ways to overturn the law. By constitutional amendment which would require 3/4 of the States to ratify (never going to happen) or for unelected SCOTUS to overturn itself, which is equally unlikely. So, at this point anything short of a complete overhaul of the system will not effect change.
As for most other issues, gay marriage, prostitution, drug use, etc. I think for any political decision one must decide if the costs of enforcing such a law would be worth the fight. The kinds of invasion on people's privacy, the false convictions and the tyranny are often far more evil than the "sin" we are trying to stave off. It is also problematic because it prohibits the possibility of the Holy Spirit motivating someone into repentance.
So, generally, yes you can be libertarian and also be a Christian, but there are certain Christian principles which it is best to not compromise, particularly the sanctity of life. However, as Christians we're only required to watch our own actions not others.