“Barbenheimer” isn’t the only phenomenon at the July box office.

Over the last four weeks, Angel Studios’ “Sound of Freedom,” an indie film that has drawn the support of former President Donald Trump and other conservatives, has captured nearly $150 million in domestic ticket sales.

The figure may seem small against Hollywood blockbuster performances from Warner Bros.’ “Barbie” and Universal’s “The Super Mario Bros.,” each of which has grossed several hundred million dollars, but it’s a solid theatrical run for a film that only cost $14.5 million to make.

It’s especially impressive considering Paramount’s Tom Cruise vehicle “Mission: Impossible — Dead Reckoning Part One” has tallied less than $140 million since its July 12 release and Warner Bros.’ DC Comics tentpole “The Flash” which barely topped $100 million domestically.

“Sound of Freedom” is also on the heels of Disney’s “Indiana Jones and the Dial of Destiny,” which has generated around $167 million in box-office grosses in the U.S. and Canada.

“Angel Studios deserves a tremendous amount of credit for designing and executing one of the most unexpected indie box office runs in years,” said Shawn Robbins, chief analyst at BoxOffice.com.

“Sound of Freedom,” which opened over the July 4th holiday weekend to the tune of $14.2 million, saw ticket sales exceed its debut during its second and third weekend in theaters, a rarity in Hollywood. Over the last two weekends, ticket sales drops for the movie have been under 40%.

Typically, blockbuster features will see at least 50% drops each week, receiving diminishing returns until the film finishes its run in theaters.

The slow fall for “Sound of Freedom” shows that audiences who may have missed out on the flick when it first opened have heard enough positive word of mouth about it to flock to cinemas weeks later.

In fact, the film initially only ran in around 2,600 theaters and has grown to more than 3,400 over the last few weeks. For comparison, both “Mission: Impossible — Dead Reckoning Part One” and “Indiana Jones and the Dial of Destiny” opened in more than 4,000 locations, according to Comscore data.

“‘Sound of Freedom’ is a summer movie success story that wasn’t even on the radar just a few short weeks ago,” said Paul Dergarabedian, senior media analyst at Comscore. “[It] has become one of the most talked about movies of the summer a film [and its] box office revenue has surpassed that of titles with much bigger stars, brands, and budgets.”

“Sound of Freedom” centers on Tim Ballard (Jim Caviezel), a character inspired by a real-life government agent who quits his job to rescue a young girl from sex traffickers in Colombia.

Part of “Sound of Freedom’s” box-office success has been a campaign from filmmakers to urge moviegoers to buy tickets that can be claimed online for future screenings by those who may not be able to afford them. Angel Studios calls the model “pay it forward” and has sold nearly 14 million of these tickets since the film’s release, according to the studio’s website.

“‘Sound of Freedom’s’ sustained success goes to show that grassroots campaigning still has a sizeable impact in this day and age and that the movie’s core audience remains overlooked and underserved,” Robbins said.

Angel Studios’ post-promotion method isn’t the only unique aspect of its business. The studio crowdfunded $5 million in order to distribute the film after 20th Century Fox, which previously held the rights to it, was bought by the Walt Disney Co. and shelved its release. “Sound of Freedom” wrapped filming in 2018.

The anti-sex trafficking thriller has struck a chord with older audiences, many of whom have not been back to theaters since before the Covid pandemic. It has also become popular in conservative political circles. Trump hosted a private screening of the film at his New Jersey-based golf club last month.

Also in attendance were Steve Bannon, Trump’s former chief strategist; Kari Lake, a former gubernatorial candidate from Arizona who backed Trump’s claims about election fraud during the last presidential election; and Jack Posobiec, an activist and TV correspondent who promoted the debunked claim that Democrats were using a pizzeria in Washington for a child sex ring.

House Speaker Kevin McCarthy, R-Calif., also held a screening of the film last week for members of Congress on both sides of the aisle.

“Often movies come along that fill a void in the marketplace,” Dergarabedian said, echoing Robbin’s comments about underserved theatrical audiences. “‘Sound of Freedom’ benefitted not only from this but also by providing a non-typical summer style movie experience.”

Disclosure: Comcast is the parent company of NBCUniversal and CNBC.