Dean's success isn't all his fault
This USA Today article makes the point that Dean's success is as much because of his attention to the fundamentals as it is his use of innovative new techniques for organizing. I might add that Dean was blessed by a Democratic Party establishment that has become so ossified that it didn't comprehend what was happening until it was (probably) to late. I'm as big a fan of the Dean operation as anyone, but I don't believe he would be the nominal front-runner today if at least one of the establishment Dems had run a halfway decent campaign. Institutional support is hard to overcome.
The battle in the general election will be a lot tougher because, unlike the Democrats, the Republicans have a much more solid and robust political machine up and running. But, I also sense that that machine is becoming complacent in its success and is ripe for defeat.
Dean may not be able to do it. But I have seen no evidence that any other Democrat could do it any better.