SAN FRANCISCO (Reuters) - After former Senator Mike Gravel failed to make the Democratic debate stage this week, the two teens running the 89-year-old’s long-shot U.S. presidential campaign used their spot on the sidelines trying to attract new supporters through social media.

Slideshow ( 2 images )

David Oks and Henry Williams, both 18, spent Wednesday firing tweets from their seats in the debate’s Miami audience, attacking the candidates speaking on stage.

Under the @MikeGravel Twitter handle, which shows Gravel sporting sunglasses and making a peace sign, the teens mocked former congressman Beto O’Rourke and Senator Cory Booker’s use of Spanish. They blasted former Vice President Joe Biden on his civil rights record, Senator Kirsten Gillibrand over immigration and California congressman Eric Swalwell for “looking like the demonic representation of blandness.”

“Welcome to the second #DemDebate (Joe Biden goes off the rails edition),” they tweeted Thursday, now back at home in suburban New York.

The teens aim to get Gravel on the debate stage to steer the Democratic conversation to the left, particularly on foreign policy issues. The former Alaska senator wants to slash military spending and bring all troops home.

The acerbic campaign has struck a chord. The @MikeGravel account saw a bump of some 9,000 Twitter followers since Wednesday, jumping to about 109,000, and the campaign says they are nearing 50,000 unique donors. They need 65,000 to make the next debate.

Gravel does not generally approve social media posts but prefers to have a “veto” role. “He’s told us a few times to stop cursing,” said Oks.

They convinced Gravel, known for reading the Pentagon Papers into the congressional record in 1971, to make a run for the November 2020 election, reprising his 2008 effort. One of his first steps was handing over his dormant Twitter handle to them.

The digital campaign, which has spawned the hashtag #Gravelanche, posts content ranging from anti-war messages to memes of Gravel “dabbing” against a background of fire or shooting lasers from his eyes at “the 1 percent.”

“There’s a whole language to the internet that people haven’t tapped into,” said Jonathan Suhr, a 26-year-old ad designer who runs the campaign’s Instagram account, contrasting the campaign’s sharp attacks and memes aimed at younger voters with candidates who have played it safer online.

The team also is beefing up their online ads. It has spent $48,516 in total paid Facebook ads - about half what Democratic candidate Senator Elizabeth Warren spent in the last week – but aims to spend at least $100,000 by the debate in late July.