Saturday Night Live gave Dean a chance to reconsider his persona, just as they held up a mirror for Al Gore four years ago.
Gore surely ran into the problem of appearing abnormal on TV, wearing too much make-up and sighing. A key moment came in the debate where he walked up right next to Bush, while Bush was in the middle of answering a question. When Bush took a second to give a little cowboy-style nod to Gore, the die was cast. Bush was a normal, humorous guy; Gore was weird and ridiculous.
Such long, hard work is required to run for President, and it can easily all be thrown away in a second--but perhaps only when that second confirms long-held suspicions.