At first glance, the Clintonian grass roots seemed to have organically sprouted in anger. But closer inspection yielded traces of Miracle-Gro that led to the sixth floor of a building in the Flatiron neighborhood of Manhattan.
There, surrounded by start-up tech companies, “Star Wars” posters and flat-screen televisions fixed on cable news, Peter Daou sat with his team at a long wooden table last week, pushing the buttons that activate Mrs. Clinton’s outrage machine. Mr. Daou’s operation, called Shareblue, had published the article on Mr. Trump’s comment on its website and created the accompanying hashtag.
“They will put that pressure right on the media outlets in a very intense way,” Mr. Daou, the chief executive of Shareblue, said of the Twitter army he had galvanized. “By the thousands.”
In the sprawling Clinton body politic, Shareblue is the finger that wags at the mainstream news media (“R.I.P. Political Journalism (1440-2016)”) or pokes at individual reporters. It is a minor appendage, but in an increasingly close race for the presidency, it plays its part.
And it is already warming up for the biggest event of the general election so far: the first debate, on Monday night. It has already published a piece calling on moderators to fact-check Mr. Trump on the spot, and will continue through debate night, whipping up support online with the hashtag #DemandFairDebates.
Shareblue is owned by David Brock, the onetime Clinton critic who remade himself into a Clinton supporter and architect of a conglomerate of organizations designed, he said, to be the liberal answer to the conservative messaging of Fox News.
The Brock network includes his Media Matters for America watchdog website; two pro-Clinton “super PACs,” the opposition research outfit American Bridge and the pro-Clinton fact-checking and reporter-spamming operation Correct the Record; and Shareblue, which filled the need, Mr. Brock said, for a progressive outlet that spoke directly to the grass roots and which “was avidly and unabashedly pro-Hillary.”