Definitely worth reading the whole review (and, I'm sure the book itself!). My bold.
Most important of all, they pioneered on-line money-raising. Every time something unusual happened (when some pundit would disparage the "kiddie corps" running the Dean show, say) the Web site staffers would "put up a bat" on the home page—a picture of a baseball bat, empty like a United Way thermometer in front of a town hall, which they would fill with red as the contributions would come in from people taking a few minutes to read the blog from their home or office computers. The supporters of the Dean campaign easily raised more money than their opponents in the early primaries and caucuses, and for the first time in recent political history, they did it largely with $20 and $50 and $75 contributions from across a large base of his ardent fans. Suddenly ten thousand people with passion and $100 apiece could match a big PAC or a patio full of Hollywood stars.
The reason the Dean campaign collapsed in Iowa, the authors argue persuasively, was largely that the new kind of campaign he was assembling threatened so many powerful people, from rich donors used to the kingmaking power their money gave them to "media advisers" unhappy at seeing their conventional wisdom ignored.
Jerome and Kos tell the story of the series of TV ads that helped turn the polls against Dean; they were sponsored by a mysterious new group called Americans for Jobs and Healthcare and they showed, among other things, the face of Osama bin Laden in order to argue that "Howard Dean just cannot compete with George Bush on foreign policy." A few months later when mandatory financial reports finally emerged, it turned out that the ads had been financed by supporters of John Kerry and Richard Gephardt and organized by the "disgraced, corrupt former New Jersey senator Robert Torricelli." All in all, the backers of the ad had given more than $8.7 million to the Democratic Party in the previous few years. Dean made plenty of political gaffes on his own but he had been eliminated by powerful Democrats.What is striking, however, is that most of his supporters didn't desert the Democratic Party after his defeat. Instead, when the Dean campaign Web site went dark a great many shifted over to Daily Kos and they started to volunteer for John Kerry— not with the same affection they'd felt for Dean, but with much dedication. I spent the week before the general election in Columbus, Ohio, and virtually everyone I talked to who was out knocking on doors for Kerry had begun the year supporting either Dean or the other Internet favorite, General Wesley Clark.
And many of them didn't drop out when Kerry lost the election, either. Instead, they concentrated on Dean's race for chairman of the Democratic Party, a post that had in recent years been mainly of interest to political insiders. The incumbent, Terry McAuliffe, retired after his failure in the 2004 elections, and the general consensus was that the 447 voting members of the relevant party committees would turn to yet another veteran of the inbred and centrist world of Democratic Party technicians, bland pols, and full-time fund-raisers. Jerome, on his widely followed MyDD blog (where Kos had begun his blogging career by posting comments), started handicapping the race; other bloggers began to study the records of Dean's rivals. One of them, Leo Hindery, for instance, was a prototypical fat cat. According to Crashing the Gate, he turned his Gulfstream around in midair while en route to a Democratic caucus when he learned that the blogs had revealed he was a chief backer of the ad linking Dean and Osama. When Dean eventually won, he said, "This party's strength does not come from consultants down. It comes from the grassroots up." In essence, this new force had lost the primary, but made it clear that it could continue to fight. "Dean was the first to break through and get inside the heretofore closed world of the party," Kos and Jerome write. "He won't be the last."
http://www.nybooks.com/articles/18910