Putting aside any lingering concerns about disagreements between the DNC and the DCCC, I think it's safe to say that Howard Dean took a pretty big gamble over the last two years, and after Tuesday's results, he looks pretty smart.
Dean's "50-state strategy" was one of the more contentious points in the party of late. The idea was straightforward enough: build up the party over the long-term by investing in infrastructure. With DNC money, state parties received resources and staff that they'd never seen from the national office before, even in, especially in, states where Dems have fared poorly in recent years.
The party had made noises about doing this before, but there was never a good time. The next campaign cycle was always immediately more important. The response was always, "Maybe after this cycle." And as soon as that cycle was done, the party began focusing on the next one.
The party had its doubts, Dean decided to take a leap of faith. For the Democrats' future, it was the right call.