What does a religion whose leader is a Suffering Servant, God in flesh, redeemer of man's self-centered sinfulness by an agonizing death on a common cross, have to do with partisan politics? He respected the reigning regime but embraced no political structure; he advocated no political or social revolution, nor any plan for a new social order on earth; he said nothing about war, and he took up no social cause--not even slavery.
Instead, he called for the establishment of justice and peace through the conversion of minds and souls; he called for followers who would leave behind everything else, give no thought to status, have no worry for even the necessities of life, embrace a life of of suffering, and follow him wherever he might lead.
How was it that a religion so austere and demanding, so contemptuous of worldly goods and status, so bent on service and chastity--so impractical--converted the ancient world? As Russell Kirk noted, one cause of the success of Christianity "was that its appeal, unconnected with political systems, became universal."
Beware then of any connection with a particular political system, which by its nature destroys the universal appeal and message of the Christian faith. To identify Christian causes with any political party is to undermine evangelization.