When the producers of the immersive musical “KPOP” surveyed the map for a city in which to prep for a leap to Broadway, they put a pin in Washington. When the producers of a new musical with a Britney Spears songbook, “Once Upon a One More Time,” went on a similar search, they homed in on the same city. And when the producers of “A Strange Loop” were seeking an out-of-town venue for their Pulitzer Prize-winning musical, they found their way to a stage in the nation’s capital, too.

All of which explains why, come this holiday season, an extraordinary convergence will occur in the storied annals of Washington as a tryout city on the road to Broadway: All three shows will be running simultaneously in the District. And just as remarkably, all three will be strutting their stuff under the auspices of highly regarded nonprofit theater companies — not via the Kennedy Center or the National Theatre, the more traditional sites in the city for pre-Broadway runs.

“KPOP” will be staged by Signature Theatre, borrowing the Anthem concert space on the Wharf; “Once Upon a One More Time” will be performed in Shakespeare Theatre Company’s larger venue, Sidney Harman Hall; and “A Strange Loop” will run in the intimate confines of Woolly Mammoth Theatre. What these multiple engagements suggest is that as theater returns to robust live-ness, Washington has been cast in a significant role once again, as a test-market locale with sophisticated theater tastes.

“Getting the responses from an audience in Washington really helps inform the kind of response we could expect in a New York audience,” said Joey Parnes, a veteran Broadway producer and general manager and one of the lead producers of “KPOP, The Broadway Musical.”

“One of the reasons to bring a show to a regional theater is not only to give the writers a chance to reconceive it,” he says, “but to learn from the audience, to adjust it so that it’s the best version of itself. An audience in Washington, D.C., does that.”

The psychic assets attached to each of these projects make the odds favorable for a future beyond D.C.: “KPOP,” a musical set in the world of South Korean pop music, with a score by Helen Park and Max Vernon and book by Jason Kim, enjoyed a successful run off-Broadway at Ars Nova in 2017. “Once Upon a One More Time,” featuring a book by Jon Hartmere and direction and choreography by Keone and Mari Madrid, has a fractured-fairy-tale setting and Spears’s pop hit songbook. And Michael R. Jackson’s “A Strange Loop” boasts that Pulitzer — and up-to-the-minute conceits, set in the mind of a theater-loving, neurotic, Black gay writer.

For these nonprofit theaters, there are potential rewards, too, and not only because they typically receive a weekly royalty if the show graduates to a commercial run. Far more readily than straight plays, musicals are the golden tickets these days to American theater’s broadest cultural relevance. Look no further for confirmation than the juggernaut “Hamilton” — birthed in 2015 at the nonprofit Public Theater in New York.

“The themes of this show align with things we want to be talking about,” said Maria Goyanes, Woolly Mammoth’s artistic director and a Public Theater alum, of the company’s landmark collaboration on “A Strange Loop.” “And I very much want Woolly Mammoth to be influencing the cultural conversation that is happening in this country.”

The partnership in musical development between commercial producers and regional nonprofit theaters has been advancing over the years, as an older tradition recedes a bit — when New York producers booked theaters in one or a series of cities and paid the full freight of a tryout period. Washington has been a microcosm of the changing landscape: Decades ago, shows as varied as “West Side Story” and “A Funny Thing Happened on the Way to the Forum” made formative stays at the National. Occasionally, producers still opt for the more traditional route, booking the National for a tryout commercial run, as in 2013 with Tom Kitt and Brian Yorkey’s “If/Then” and, in 2018, “Beetlejuice,” with a score by Eddie Perfect.

Today, Arena Stage can be as likely to shelter a musical on the way to Broadway as the National. In fact, Arena was the original staging ground in 2015 for “Dear Evan Hansen,” an ongoing Tony-winning hit in New York and on the road. The show restarts Dec. 11 on Broadway, and the tour returns to the Kennedy Center in August 2022. Signature, too, was a testing site in 2016 for Disney’s musical adaptation of the film “Freaky Friday,” although the show was built for touring rather than Broadway.

Some dissenters decry the practice of nonprofit organizations welcoming commercial ventures. The argument is that outside producers are taking advantage of a platform that was created to shield theater from sheer mercenary concerns. Still, the arrangements seem here to stay. And as evidenced by some of the prestigious D.C. companies taking part, the tryout model is moving into even more rarefied corners of the industry. Usually, the deals require producers to share the costs of the show with the theater companies, as will happen with the three musicals running in D.C. in November through January.

With “KPOP,” it was both the city and the space that figured in the decision. Signature had an existing deal with the Anthem, a flexible concert venue that can accommodate up to several thousand ticket holders. But the pandemic scuttled a plan to stage a revival of “Mamma Mia!” there last summer. After discussions started between “KPOP” — in which a concert is part of the story — and Signature, the Anthem project was given a second life.

“The opportunity to do it at the Anthem — it just seemed so perfect,” said Tim Forbes, a producer who has been involved in “KPOP” since its inception at Ars Nova, and its development by the Woodshed Collective, an immersive New York theater company. The musical is undergoing some restaging, as the original production was on two floors, with audience members divided into groups and moving through the space. The Broadway-bound version is being redesigned, its producers said, with the ¾ -round Circle in the Square Theatre in mind.

Parnes added: “This turned out to be a great opportunity for Signature, for the Anthem and for ‘KPOP’ in a space that we could definitely approximate Broadway. It was too delicious to turn down.”

Imagine, then, a time around Christmas, when a Washington-area theatergoer might find a delicious opportunity, too: to go from show to show to show, and get an in-depth exposure to a Broadway yet to come.

But also, exposure to what theater-makers in D.C. like to think of as a community of expanding possibility. As Goyanes put it: “Woolly Mammoth is an alternative to mainstream theater, and we are always working at shifting public perspective. This is one of the ways of doing that. With everything that is happening in the world, the mainstream is shifting.”