In a posting Monday night, Macon Phillips again pointed the finger at “outside groups of all political stripes” but downplayed the backlash over the unwanted e-mails.

“An ironic development is that the launch of an online program meant to provide facts about health insurance reform has itself become the target of fear-mongering and online rumors that are the tactics of choice for the defenders of the status quo,” he wrote. “Despite reports by some bloggers and others in the media that have invoked a variety of sinister conspiracy theories, more people signed up for updates last week than during the entire month of July.”