Online organizing “still comes down to what you’re selling,” said Bruce Mehlman, a tech lobbyist who was assistant secretary of commerce in the Bush administration. “Obama, as an idea, was wildly popular. Will that work with health care reform?”

Mehlman is skeptical, but he added that a network of 13 million backers should not be discounted: “In the election, they mastered the tools better than anyone has so far.”