It’s unlikely many people in the audience at a New Hampshire town hall meeting noticed anything amiss Monday. But a 90-second confrontation between an aide to Kentucky Sen. Rand Paul and a Democratic operative jumped out immediately online.

As shown in the brief video, a tussle between the two ended with the Paul staffer licking the camera.

“Just when you thought Rand Paul’s campaign couldn’t get any stranger, his senior staffer in New Hampshire decided to taste our tracker’s camera lens today,” said Preston Maddock, a spokesman for American Bridge 21st Century, the liberal group that had sent the operative. “It was truly bizarre, creepy and unprofessional.”

Despite American Bridge’s indignation, it was exactly the type of moment they were looking for: embarrassing, awkward and buzzworthy.

Opposition researchers, as the practitioners call themselves, have long been part of campaigns, digging up dirt on rivals and passing it to reporters and activists. But in recent years, they’ve become active participants as well, sending one-person camera crews to document as many of the rival candidates’ campaign stops as possible and maybe even unintentionally provoke them.

The same American Bridge tracker from the New Hampshire town hall last chased former Massachusetts Sen. Scott Brown as he canoed on the Contoocook River during his failed attempt to return to the Senate representing New Hampshire.

It’s an equal opportunity pastime. American Bridge and its Republican counterpart, America Rising, are each million-dollar organizations dedicated to documenting the stumbles of the presidential candidates and those around them. The goal is to discredit the candidates to voters and to amplify their errors with raw footage of candidates behaving oddly.

The biggest catch—and one that only encouraged the trend—was in August of 2006, when then-Sen. George Allen of Virginia introduced his audience to a tracker from Democratic rival Jim Webb’s campaign. The tracker’s name? S.R. Sidarth.

“This fella here, over here with the yellow shirt—Macaca, or whatever his name is—he’s with my opponent. He’s following us around everywhere,” said Allen, who went on to lose to Webb.

Critics said “macaca” was a slur against the tracker, who is Indian-American.

Other campaigns and political parties quickly identified the value of sending a staffer to tail rivals with a video camera, just in case they fumbled or responded to harassing questions. The addition of YouTube and other video sharing services only hastened the ease with which campaigns could share video to supporters and reporters alike.

It has changed how candidates interact with voters and reporters alike.

In 2010, Senate hopeful Sharron Angle fled journalists in Reno. Trackers from the Nevada Democratic Party documented the Republican’s refusal to answer questions from reporters. The video of reporters chasing Angle from an event, and her speeding away in a white SUV, reinforced opponents’ arguments that she was not up for the job.

In 2012, Republican Rep. Allen West of Florida was asked during a town hall appearance how many lawmakers were Marxists or socialists. West took the question seriously: “There’s about 78 to 81 members of the Democrat Party that are members of the Communist Party.” The local news carried his comments, but the addition of video—easily shared online—made it a topic on social platforms such as Twitter and Facebook. West narrowly lost his re-election bid.

Candidates can even get in trouble for trying to avoid confrontation.

In 2014, as cameras rolled, immigration activists confronted Paul while he was campaigning in Iowa with Rep. Steve King. The activists, who were brought to the country illegally as young children and want to be treated as citizens now, confronted King about his views on immigration.

Paul, who was sitting across from King, looked to communications aide Sergio Gor. Taking his cue, Paul put down his burger, pushed back his plastic picnic chair and walked quickly away from the table. King, meanwhile, stayed and sparred with the DREAMer. The video quickly ricocheted around the Internet.

American Bridge officials were hoping Monday’s licking incident would have similar viewership.

Asked about Mondays incident, Gor declined to identify the licker or say if he worked for the campaign in an official capacity. Instead, he issued a statement completely unrelated to the incident.

“Sen. Rand Paul visited New Hampshire today to accept the endorsement of 20 New Hampshire state representatives who support his run for the White House, and to visit with and take questions from the voters,” Gor said. “It was a great day of events.”

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Write to Philip Elliott at philip.elliott@time.com.