Grayson gets his power from being noticed.
Alan Grayson has one skill in life. Comparing people to Nazis. If Alan Grayson were forced to write a sentence in which he didn't have to compare anyone to a Nazi, the Confederacy or Genghis Khan, his hands would seize up, his eyes would roll back into his head and he would pass out.
Grayson has nothing to say. The limit of his contribution is comparing something to Nazi Germany. Then someone gets outraged by his idiocy and he gets to do it again.
There's an easy way to defeat him. It's the same way you defeat any troll. Stop paying attention to him.
It's not as if Alan Grayson is going to make a compelling argument when you aren't paying attention. It's just not going to happen. All he's going to do is keep chanting "NAZI NAZI CONFEDERACY TEA PARTY REICH WING SARAH PALIN NAZI NAZI" because he has half the brain cells of a YouTube commenter and twice as much exposure.
Alan Grayson is the embodiment of Godwin's Law. So much so that it should probably be renamed Grayson's Law. He sent out a dumb fundraising pitch that would have been ignored if not for the outrage. It would have been better if Grayson had been ignored and if he had been forced to spend his time accusing random pigeons of being Nazis.
Grayson gets his power from being noticed. Then he can pretend to be controversial, when he's really a one-note troll. Stop paying attention to him and he becomes just another obscure member of Congress.