I'm no more sanguine about an active pastor being elected to the US Senate from the other side of the political spectrum. Raphael Warnock seems like a good and intelligent person. But there is simply no way that Christian leaders and denominational bodies can prevent the cause of the Gospel being hurt when their political engagement seems to say, "To follow Jesus, you have to agree with these political ideas."
That's an example of "syncretism": conflating the Gospel of new life through repentance and faith in the God revealed in the crucified and risen Jesus with human inventions--political philosophies, human thoughts, political idols.
To follow Jesus, according to Jesus Himself, we pick up our crosses and follow. We confess and turn from our sin and embrace the new and everlasting life it's only His to give.
As much as I love and revere Dr. King, the moral arc of the universe does not bend toward justice. This world is fallen. We are born sinners. We're out for number one, which is why when God came into the world, calling us into His kingdom of love, grace, and justice, we took a pass and nailed Him to a cross to die. By our arrogance, indifference, and antipathy to God and the people God made and for whom Jesus died and rose, we still crucify Him.
We all have our political preferences. As long as we see them as our preferences and don't pretend that they have the imprimatur of heaven on them, we see and act aright, it seems to me.
But when pastors become king-makers or run for office, which I, to my shame, once did and for which I have repented, we hurt the cause of Christ.
In short, I hope that all of us called to positions of servant leadership in Christ's Church--to ministries of Word and Sacrament--will renounce the pursuit of political power and instead, embrace Jesus and His Gospel as our cause.