And Dean offered plenty of angles. He ran his mouth; he ran away from the centrism that defined his gubernatorial record, a record that came out and offered an irresistable opening for a "which is the real Howard Dean" thumb-sucker; he trumpeted his position on the war quite loudly, though the nuts and bolts of his policy were not so far from Bush's -- so much so that his speeches seemed to cry out for a disclaimer ("This war-related stance not valid in all states. Read your prospectus carefully").
Really, I think what caused Dean's implosion is that his campaign was premised on pushing for attention in a crowded field, which he did by speaking loudly and ascerbically. I don't know if you play Bridge (the card game) at all, but part of the difficulty is what to do when your opponents hold the lead. Ideally, you want to time your high cards, since once you have the lead, you need to exploit it. That is, it's not worth throwing your ace until you know how you can play the rest of your hand. Dean's strategy was to get noticed by throwing his aces. But once you win a trick, you have the lead; your strategy has to change. Perhaps his campaign is discovering that now. It seems likely, since the focus seems to be shifting to tighter troop control, centralized command, and message discipline (plus, no St. Vitus Dance speeches).
Dean may not be dead, but he's not sitting pretty anymore. If my guess is correct, his campaign spent all its time figuring out how to get the catbird seat, and no time figuring out what to do once he was there.