I know nobody is taking this overly seriously, but since I'm from the state and argued it elsewhere I suppose I should do so here. The clip is misleading, and considering how lovingly the right wing picked it up it's not hard to guess why.
In context it's obvious that the man is making a joke, and while his illness probably did contribute to the difficulty on display, the surrounding topics of conversation make it clear that he's anything but unintelligent. The way this has been framed to insult a very sick man is really disgusting. I'm not sure why it's hit a nerve, but it has, and the people pushing this line should be ashamed.
The link to the full video is here:
http://bit.ly/9rXLFe , with his bit starting around 1:31. It loads incredibly slowly however.