Perhaps the Klintoons feel more comfortable having someone who "understands" that politics is more about telling people what they want to hear, and spewing a constant stream of sound bytes that smear the opposition, than it is about anything involving integrity, leadership or other such old fashioned crap. </sarcasm>
Dean certainly threatened the Klintoon's control of the party more than the other candidates, and threatened to gain independent sources of money, from his working the web.
I reckon Hitlary is more concerned with controlling the big money than she is with ensuring that no other 'Rat wins this time around. She should be pretty confident that no other 'Rat is going to win in '04 if she decides they shouldn't.