What happens if Dean fails to win the primaries, the Dems nominate someone more "electable" (in the eyes of the DLC) and the party still loses?
Say one of the more establishment-friendly candidates wins the primaries. Dean quietly goes back to Vermont. What happens to his organization? What happens to his ideology and his thousands of supporters?
Virtually all of his supporters will vote for the Democratic primary winner of course. Many will even go work for him. But what about the ideology? What about the attitude that drew so many to Dean in the first place? In many ways Howard Dean is a protest candidate-- the success of his candidacy relies in no small measure on the anger felt by Democrats against the entrenched incompetence of the leading members of their current party. His broad axis of support is sprinkled with people from various parts of the Democratic base who are simply tired of being ignored, especially for the dubious electoral results of the past couple years.
Now none of this matters that much if the nominated Establishment Democrat wins the election. But what happens if they lose? The battle to put Dean down would be hard fought and it would leave some sore feelings. To go through all of that only to see the Democrats fall in defeat yet again would be a horrible thing. And, with such a large, committed, and pissed off group after them it would be hard for the party's current centrist leadership to retain its position of power. But without Dean channeling the resurgent liberal ideology into a fairly moderate message, I think it's very likely that the result of a Howard Dean primary loss would be a takeover of the party by "real" liberals. People with the ideology of, say, Kucinich or Sharpton would start to gain much more influence than they do now.
Ultimately, this makes the attacks against Dean by groups like the DLC seem a little bizarre. It seems to me that, now that Dean has let the "genie" of empowered liberalism out of the bottle, 2004 will be a choice between Dean's brand of angry left-of-centrism or full-scale liberalism. You'd think that From, et al. would much prefer the former.