The Good News of Jesus is political--profoundly so. The politics of Jesus are pointed. Jesus has something powerful to say about wealth, poverty, justice, the value of life, our regard for aliens and strangers, our responsibilities to our local and global neighbors, communities and governments, etc. (for a kickstart, read Matthew 5-7; read on if you're still standing).
The politics of Jesus are such that they, if taken at face value, necessarily prevent partisanship among those of us who make it our goal and pattern to follow him. It is not that Jesus is not specific in regard to critical social issues and Biblical justice. It is not that Jesus' politics are otherworldly. It is that Jesus' way is not merely a program, not a point-by-point platform, not a coercive agenda. It is that his words and way defy and transcend every fallen ideology.
Still, the church is not above politics (rightly understood), for, when we are at our best, we emphatically value people and principles and processes in a way that Jesus demonstrated and taught--and these are, more often than not, in contrast to all partisan politics and policies. The idolatry of ideology (along with images and institutions) is one the fallen "principalities and powers" which William Stringfellow identifies that are to be called out and redeemed.
Jesus' politics unmistakably challenge all fallen ideologies and status quo, including the institutional micro-ideologies of churches and faith-based groups. The politics of Jesus, however, do not and cannot be claimed or harnessed by mere political parties or politicians--or church representatives who favor one party or politician over another or think their chosen party is God's instrument.
At this point in time, I do not see any partisan ideology that is worthy of any Christian's adherence. At the same time, each of us as citizens have a responsibility to engage fully in civic discourse and wrestle with what we feel is best for our communities and world amid fallen people and systems.
It should be the burden of each of us as Christians to guard our own hearts, fully contemplate the matrix of what Jesus lived and taught in the context of our own times, and carefully and caringly enter into civic discourse from a clearly nonpartisan perspective. But avoidance of reflecting Jesus' values, assessments, priorities, etc. in the public arena is not a valid option, it seems to me.
For more on this perspective, read "The Politics of Jesus" by John Howard Yoder, "The Politics of Spirituality" by William Stringfellow, and "The Upside Down Kingdom" by Donald Kraybill.