The effort by the team that posed as Guccifer to disseminate the fruits of the audacious cyberattack shows how aggressively the Russian operatives worked in 2016 to interfere with the presidential election. They showed dexterity in navigating their way through the national political debate and an increasingly sophisticated understanding of American electoral politics.

In addition to WikiLeaks, the Russians made contact with Americans who held sway both in Republican circles and with Mr. Trump, the indictment says. It does not assert that the Americans knew that Guccifer 2.0 was a creation of Russian spies.

Those figures included Roger J. Stone Jr., the longtime Trump friend who exchanged messages with Guccifer during the campaign but said in an interview on Saturday that he did not believe at the time that Russian state actors were behind it. “I originally thought he was a Romanian hacker because that’s what he claimed to be,” Mr. Stone said.

There was Lee Stranahan, who is now a co-host of “Fault Lines” on the Russian-owned Sputnik radio network but back then was at Breitbart News, whose chief during that period, Stephen K. Bannon, joined Mr. Trump’s campaign that August.

The indictment mentions that Guccifer 2.0 had sent some documents to a lobbyist in Florida, which had been previously reported. But it also reveals that a congressional candidate whom it did not name connected with the operatives, looking for stolen documents about a political opponent, which were then sent.

Using Guccifer 2.0 as their main means of communication, the Russian agents had regular contact with both conservative and mainstream journalists, the indictment said. In one case, it said, the Russians gave an unidentified reporter a password to view documents. The Smoking Gun said in a Twitter message that it was the “reporter” in the reference. In another case, according to the indictment, the Russians conferred with a writer about the timing of one planned leak; Mr. Stranahan announced on Twitter that he was the writer, then at Breitbart.