WASHINGTON - Besieged by unflattering stories about the launch of President Barack Obama's healthcare programme, the White House saw a news report that it wanted to swiftly knock down.
It was from NBC, which said that Obama had overpromised when he said Americans who liked their insurance could keep it, and that the president knew that many people would see their coverage change.
White House officials quickly began firing off a barrage of tweets on Twitter, which has become one of the administration's most potent and relied-upon weapons in trying to shape public opinion and media reports.
Josh Earnest, the principal deputy press secretary to Obama, began the assault with a series of tweets that said the healthcare law did protect Americans against changes in their coverage - unless insurers altered such coverage.
"NBC 'scoop' cites normal turnover in the indiv insurance market," Earnest tweeted to his 9,500 followers on Twitter.
The message was retweeted 166 times, potentially reaching another 164,000 people, according to Twitonomy, a Twitter analytics tool.
During the next hour, White House staffers would tweet and retweet messages about the story more than a dozen times, including tweets directly to the NBC reporter.
The debate continues over whether Obama has been misleading about the healthcare law. But it's clear that in many ways, Twitter has become as important in the West Wing's communications arsenal as daily press briefings. Twitter's 140-character messages are faster than a press release, with broader and more direct reach than appearances on cable television.
Under a strategy championed by Obama's senior adviser Dan Pfeiffer, the White House has doubled its footprint on Twitter since July, giving official accounts on the social media web site to more than a dozen additional communications staffers.