I don't really understand this point of Kos's:
Dean isn't the DCCC or DSCC. His job isn't to win elections in 2006. As head of the Democratic National Committee, his job is to build a national party.
Republicans haven't abandoned a single one of their supporters. You could live in the Bluest part of Berkeley or Madison or Cambridge, and the party will communicate with you via mail and on TV and the radio. Drive into San Francisco over the Bay Bridge, and you're met with a billboard advertising Michael Savage's racist radio show.
Savage is a private entity. The billboards are paid for by his radio company, which seeks to make money off his advertisers by attracting more listeners. It has nothing to do with the Republican party.