No one knows who you voted for, unless you tell them (in theory, anyhow). So long as the Doc doesn’t actually demand that patients tell him how they voted; he’s not discriminating against anyone, who still wants him to treat them, despite his sign.
The Dr. has said that even if he knows for sure a patient voted for Obama, he will not turn him away. He has a pretty good way of demonstrating the world is full of people who will interpret his actions in all sorts of ways he never intended. I don’t know if he did this on purpose, but it sure is enlightening.
Besides, as I posted already, does Grayson believe that ONLY black people voted for Obama? How else could it be “racist” to discriminate against people who voted for Obama, anyway?