The grainy first-person testimonial arrived at 2 a.m. in late June. A 40-year-old man with a thick Southern accent — shirtless, the red ember of his cigarette glowing in the green twilight between drags — looked into his smartphone and began talking.

“Hi, my name is Josh and I live in North Carolina and I voted for Donald Trump — my bad, fam,” he begins, before explaining that this November will mark the first time “ever, ever” that he will vote for a Democrat. “If Joe Biden drops out and the DNC runs a tomato can, I will vote for the tomato can, because I believe the tomato can will do less harm than our current president.”

The unsolicited video submission to a group called Republican Voters Against Trump is just one small part of a broader “Never Trump” rebellion that began four years ago as a largely ineffective cadre of appalled Republicans, but which has transformed in recent weeks into a potentially disruptive force in this year’s presidential race.

Groups such as the Lincoln Project and Republican Voters Against Trump — which is focused on first-person testimonials like Josh’s — emphasize guerrilla tactics and scathing ads as they troll the president. The movement seeks to build a national political operation to oust both the president and his supporters in Congress, with a particular emphasis on persuading white suburban voters who consider themselves true Republicans to break from the president, according to interviews with more than a dozen anti-Trump advisers and allies who are involved in the planning, some of whom spoke on the condition of anonymity to describe private discussions.

Advisers to the Lincoln Project, which they say has about 30 employees and raised $16.8 million this quarter, will soon expand to include ground operations. They are coordinating over 2,500 volunteers in Michigan and plan to next target Republican Sens. Susan Collins (Maine), Joni Ernst (Iowa), Thom Tillis (N.C.) and Lindsey O. Graham (S.C.), who they see as vulnerable after his challenger, Jaime Harrison (D), pulled in a staggering $13.9 million since April.

But most of the project’s efforts so far have been centered squarely on Trump — evidenced by their surgical strike ads airing on Fox News in Washington, which are aimed not at persuading disaffected Republicans but simply at needling the president.

One 45-second spot focuses on Trump’s health, featuring footage of the president walking haltingly down a ramp at the U.S. Military Academy at West Point, with a narrator warning, “Something’s wrong with Donald Trump. He’s shaky, weak, trouble speaking, trouble walking.”

After the ad ran — helping to inject questions about the president’s fitness into the cable news cycle — Trump went off script for nearly 15 minutes to address his West Point performance at a rally in Tulsa, which was intended to reset Trump’s stalled reelection bid.

As the campaign unfolds, the movement’s influence will be tested, however, as many Republicans rally around the embattled president and as former vice president Joe Biden, the presumptive Democratic nominee, becomes a more high-profile target of GOP attacks.

Two Republican officials who work on House and Senate races said the Lincoln Project and similar groups are more effective at rattling the president than affecting the electoral landscape. “They don’t have juice,” one of them said. A second added that groups aren’t spending “big money,” and that Trump — if the election were held right now — would face “a bloodbath” regardless of the groups’ various efforts.

And it remains to be seen just how much influence the groups will ultimately have with the only metric that matters — persuading voters — rather than simply generating Twitter buzz and titillating the media.

The White House declined to comment on the record, although privately both administration officials and outside allies are dismissive of the groups — especially the Lincoln Project — which they deride as “scam PACs” run by “beltway swamp creatures whose candidates can’t win,” in the words of one senior administration official who spoke on the condition of anonymity to share the administration’s view of the groups.

Erin Perrine, a Trump campaign spokeswoman, was similarly critical.

“This is the swamp — yet again — trying to take down the duly elected President of the United States,” Perrine said in an email statement. “President Trump is the leader of a united Republican Party where he has earned 94 percent of Republican votes during the primaries — something any former president of any party could only dream of.”

Still, the leading members of the anti-Trump bloc believe they can be helpful to Biden by sharply attacking Trump on divisive and controversial topics that campaigns typically avoid, such as the president’s physical health. The Biden campaign, for its part, sees little downside to these outside groups going after the president, an official said.

And unlike in 2016, when many of them bandied around independent candidate Evan McMullin, whose campaign failed to dent Trump, their work this time is aimed on damaging Trump’s standing rather than on offering a Republican alternative or challenging Trump at the party’s convention.

Other groups in the anti-Trump wing include Right Side PAC, which is led by Matt Borges, former chairman of the Ohio Republican Party, and advised by former Trump White House communications director Anthony Scaramucci, a financier who has become a Trump critic. And there is 43 Alumni for Biden, formed by officials who worked in the George W. Bush administration.

The Lincoln Project was founded by Republican strategists John Weaver, Rick Wilson, Steve Schmidt and former New Hampshire Republican Party Chair Jennifer Horn. Lawyer George T. Conway III, who is married to White House counselor Kellyanne Conway, is also involved.

Republican Voters Against Trump, which was founded by longtime conservative and self-described “Never Trumper” Sarah Longwell, has concentrated almost entirely on sharing testimonials from traditional Republicans who voted for Trump in 2016 but are planning — sometimes reluctantly — to support Biden in November.

The group also includes William Kristol, a conservative commentator; Tim Miller, a Republican operative who worked on Jeb Bush’s 2016 presidential campaign; and Mike Murphy, a longtime Republican strategist.

Longwell said she spent most of the three years after Trump’s election trying to understand what happened and conducting focus groups with voters who supported Trump in 2016 but now rate his performance in office as “somewhat bad” or “very bad.” As her group began testing ads, they quickly realized that slick commercials were often less persuasive than raw testimonials from fellow Republicans with similar doubts about the current president.

They worked for several months to recruit 100 first-person testimonials, largely shot on smartphones — but now have more than 400 videos, many of them unsolicited.

“The ones that really stand out tend to the be the ones where someone is really grappling with the decision, someone saying, ‘I’ve been a Republican my whole life, I’m passionate about this party, I’m passionate about these ideas, but I just can’t vote for Donald Trump,’ ” Longwell said. “It feels like they’re getting something off their chest, and people really respond to that authenticity and the realness of that.”

The group, which has begun airing testimonials on television and online in North Carolina and Arizona, plans to spend $10 million to $15 million and also go on the air in Pennsylvania, Michigan, Wisconsin and possibly Florida. Their target audience is largely white suburban women, a group that has already begun to move away from Trump.

On Sunday, Republican Voters Against Trump will air an ad during “Fox News Sunday,” a program Trump frequently watches, in North Carolina and Arizona highlighting 15 Republicans who voted for Trump in 2016 but will now vote for Biden.

“It’s okay to change your mind,” the ad ends. “We did.”

The current incarnation of the Never Trump movement represents an evolution from the group that first came together in 2016 to oppose Trump with blog posts and magazine articles. After Trump was elected, many of them eventually fell into line and backed the president with varying levels of enthusiasm, both in Congress and in the activist and media ranks, seeming to relegate the “Never Trump” slogan to curio status.

When the Lincoln Project was founded in December, expectations were low. Trump’s approval rating among Republicans was sky-high, and most of his party’s lawmakers were vocally supporting him in the impeachment inquiry on Capitol Hill.

Then in early May, the project received a jolt: “Mourning in America” — a dystopian twist on Ronald Reagan’s famous 1984 “Morning in America” campaign spot — went viral, generating millions of views and drawing Trump’s wrath for its skewering of his handling of the coronavirus pandemic.

The Trump campaign issued a lengthy statement in response to the ad, saying it inaccurately depicted the federal government’s handling of the outbreak and calling those involved “scumbags” and “scam artists.” PolitiFact rated as false one of the ad’s claims that the bailout has not helped Main Street, an assessment disputed by the group.

Trump piled on, calling the group’s founders “LOSERS” in a series of midnight tweets and later telling reporters, “They should not call it the Lincoln Project. It’s not fair to Abraham Lincoln, a great president. They should call it the ‘Losers Project.’ ”

Since then, the group and others like it have been emboldened.

“It would be foolish not to take advantage of the most undisciplined president in modern history,” said Stuart Stevens, the chief strategist on Mitt Romney’s 2012 presidential campaign, who joined the Lincoln Project in May. “It’s really a national conversation and one guy — Trump — has a pulpit unlike anything, and to get him to enter into the conversation amplifies the conversation like nothing else.” Never Trump operatives also say they learned lessons from their failures in 2016, and believe the political landscape is more favorably disposed to their efforts this time. Trump now has a record for them to assail, and Biden is a more palatable candidate for some Republicans and independents who voted for Trump four years ago because they so disliked Hillary Clinton.

“Is there enormous energy to beat a divisive and incompetent president who is responsible for worsening the most devastating health and economic crisis in a generation? Absolutely. But we’re also seeing a genuine and powerful movement of Americans uniting behind Joe Biden,” said Biden campaign spokesman T.J. Ducklo. “Never Trump is translating to pro-Joe, and that is very bad news for the president of the United States.”

Inside the Lincoln Project, there has been a frenzy of activity as the group has gone from a small outfit with a couple million on hand to a viral-video production machine. Turning their attention to the Senate map is of particular importance, and a new ad this past week offers a rebuke of Senate Republicans who have lifted Trump.

“Learn their names. Remember their actions. And never, ever trust them again,” the ad urges, promising accountability for these lawmakers even after Trump is no longer president.

A Friday memo from the group obtained by The Washington Post argues that “Arizona and Colorado are off the board for Republicans” and says South Carolina, Kansas and even Alabama could be in play.

Weaver also said that “dispatching Trump does not dispatch Trumpism” and cited Fox News host Tucker Carlson, as well as Republican Sens. Tom Cotton (Ark.) and Josh Hawley (Mo.), as other potential party leaders he hopes to sideline.

“The next battle will be making sure those from his ilk do not get the next Republican nomination,” Weaver said. “Our task won’t be finished when Joe Biden takes the oath of office.”

Meanwhile, Republican Voters Against Trump has been heartened by the outpouring of unprompted videos sent their way, like the one from Josh in North Carolina. When his video first landed, some suggested some light editing, but Miller, the group’s political director, argued the video’s power was its raw authenticity.

“He’s like the Mona Lisa,” Miller said. “He’s perfect. He’s like art.”

Michelle Ye Hee Lee contributed to this report.