If that's the case--which I don't doubt--I have little doubt that he would be appalled at the field of candidates for the Republican Presidential nomination.
Mind you, I'm no fan of Obama: I think he's thrown transgender people under the bus. However, even Ron Paul--the only one of the Republicans for whom I would even consider voting--makes Obama seem like, well, MLK by comparison.
At least Ron Paul voted against the Marriage Protection Act which, had it been amended to the Constitution, would have banned gay marriage. Of course, his motives for his vote had nothing to do with any interest in LGBT rights. Rather, he didn't want to vote for another law that would have allowed the Federal Government to, in his view, usurp authority that belongs to individual states. Absent such a law, we have a few states that allow gay marriage, even if there is no Federal guarantee that same-sex couples will have the same rights as heterosexual ones.
That vote alone makes Ron Paul seem like Sojourner Truth next to Rick Santorum, Newt Gingrich or even Mitt Romney. I can just see MLK spinning in his grave.