AlterNet: The Assassination of Howard Dean:

"In the end, Dean threatened a troika of powerful institutions. He was a threat to the political parties (because he attacked Democrats' centrist drift), to media (because he criticized their cowardly reporting) and to big business (because he would roll back chummy tax-benefits for corporations). All three institutions responded with venom and destroyed Dean's candidacy. In 1968, a sniper's bullet ended Robert Kennedy's anti-establishment candidacy. In 2004, the methods used were more subtle, but just as effective. "