Asked if NN08 tried to get Mr. Obama this year, Gina Cooper, who has helped organize all three conventions, said, “Of course we did.” She added that the request was “unusual because generally people come to us.” She said Mr. Obama already had commitments (his campaign spokesman said he was preparing for his trip abroad) but noted the many panels in which his team would participate.

“There’s such a synergy between his campaign philosophy and what we’re doing,” Ms. Cooper said, though she added that the netroots were feeling an “urgency” about certain issues that Mr. Obama may not be reflecting.

Josh Orton, the political director of NN08, said: “One strength of the online community is that issues get substantive discussion, so while not everyone here will agree with Obama 100 percent of the time, we’re also not chained to conventional wisdom.”

That synergy between the campaign and the netroots has been lost of late as the media has reported about schisms between them, based on Mr. Obama’s perceived lurch to the center.

Still, despite the Obama campaign’s organizing prowess online, and its ability to raise staggering sums, the candidate’s relationship with the netroots has not always been smooth. Straw polling last year showed the netroots preferred John Edwards of North Carolina over Mr. Obama.

Part of the problem stems from a difference in style. The netroots can be reflexively confrontational and demand ideological purity.

A couple of years ago, the netroots breathed hot down Mr. Obama’s neck for staking out centrist positions. But he played it cool. In a memo in September 2005, “Truth, Tone and the Democratic Party,” which his staff posted on the Daily Kos, Mr. Obama took issue with their tactics. He wrote that Democratic candidates who wanted to win the trust of voters could not, like the netroots, demonize those who disagreed with them or be ideological pure (hat tip to Matt Bai’s “The Argument,” Penguin Press, 2007, for a great description of this episode).