Far from representing a genuine social media groundswell, however, the posts are the product of a sprawling yet secretive campaign that experts say evades the guardrails put in place by social media companies to limit online disinformation of the sort used by Russia during the 2016 campaign.

Teenagers, some of them minors, are being paid to pump out the messages at the direction of Turning Point Action, an affiliate of Turning Point USA, a prominent conservative youth organization based in Phoenix, according to four people with independent knowledge of the effort. Their descriptions were confirmed by detailed notes from relatives of one of the teenagers who recorded conversations with him about the efforts.

The campaign draws on the spam-like behavior of bots and trolls, with the same or similar language posted repeatedly across social media. But it is carried out, at least in part, by humans paid to use their own accounts, though nowhere disclosing their relationship with Turning Point Action or the digital firm brought in to oversee the day-to-day activity. One user included a link to Turning Point USA’s website in his Twitter profile until The Washington Post began asking questions about the activity.