Dim Bulb: Lawrence O'Donnell

Who: MSNBC’s Lawrence O’Donnell

What: O’Donnell mocked Ann Romney for saying that dressage — a form of horseback riding — helped her recover from multiple sclerosis. “[C]ome on, dressage does not appear in any of the more traditional courses of treatment. And if it’s true that dressage is how wildly rich people deal with this very difficult personal health problem, then why, why does the horse appear on Mitt Romney’s tax return as a business expense, that in 2010 produced a $77,000 business deduction?”