“Stuff Happens” is really happening at the Public.

David Hare‘s theatrical post-mortem of the march to war in Iraq — with a dramatis personae that includes George W. Bush, Condoleezza Rice, Colin Powell and Tony Blair — doesn’t have any movie stars in the cast, but nonetheless biz has been booming since the show went on sale March 9.

“As soon as we opened up the box office, tickets were selling at the rate that a hit show sells later in its run,” says Public a.d. Oskar Eustis, likening grosses to late-run figures for Public successes “Take Me Out” and “Caroline, or Change.”

Hare’s play comes to New York after a London preem in 2004 and a production at the Mark Taper Forum in Los Angeles last summer. The scribe has made changes to the script for the Public production, which starts previews March 28 under the direction of Daniel Sullivan.

Aside from dramaturgical tweaks, which Eustis says punch up the character and story arcs for Powell, Blair and Rice, there are changes to reflect the current political climate. The final scene, a monologue by an Iraqi exile, has been rewritten, and the interjections of prototypical characters such as the Angry Journalist and the New Labor MP, who observe the action and provide direct-address commentary, have been modified.

“Each of those has to be recalibrated, because our feeling about what’s happening in Iraq has changed immensely from a year and a half ago,” Eustis says.

The Public’s production will take place in a reconfigured version of its 300-seat Newman Theater, with the stage shifted to accommodate audience members on either side of the playing space. “It gives the show the feeling of a kind of town hall meeting,” he says.

If the strong sales keep up, the production will sell out before the show opens April 13. “It makes me think we’re doing this at the right time,” Eustis says.

‘Teen’ queen

Scott Elliott and Nellie McKay are working on a movie-musical.

In fact, it’s how they met, even before helmer Elliott cast the young singer-songwriter in the Roundabout’s revival of “The Threepenny Opera,” which began previews March 24.

Elliott, who directed the 1999 movie “A Map of the World,” thought McKay would be a good fit for a tuner-pic adaptation of Katherine Arnoldi‘s 1998 graphic novel, “The Amazing True Story of a Teenage Single Mom.” The book has been optioned by the Kennedy/Marshall Co. (which produced “Map of the World”); McKay is working on the score.

“I thought her sensibility would be a good match for this young mother,” Elliott says.

“And then as I got to know her, I thought, I bet she’s a really great actor” — a thought that led to McKay’s stage debut in “Threepenny.”

The outspoken chanteuse-turned-thesp, whose new album, “Pretty Little Head,” remains in release limbo after a public battle with Columbia, may well be the quirkiest member of a quirky “Threepenny” ensemble that includes Cyndi Lauper and Kevin Rennard, the alter ego of drag diva Flotilla DeBarge. (Acting onstage is “like tasting seaweed for the first time,” McKay says with typical obliqueness. “It’s salty. It’s got a strange consistency.”)

No timeline for “Amazing True Story” has yet been set. In the meantime, McKay faces legit critics when “Threepenny” opens April 20.

Bridging the gap

Sarah Jones‘ one-woman show, “Bridge & Tunnel,” recouped its $900,000 capitalization March 12 — quite a feat for a show that opened in late January with no big-name star and little lead time to get the word out, after landing a theater only at the last minute.

The news raises the question: You can still put a show up on Broadway for just $900,000?

“Every single entity that took part in the show — landlord, publicity, star etc. — everyone took the minimum a union would allow, or a cut,” says producer Eric Falkenstein. “There’s no way we could have done it otherwise.”

Now that the show’s in the black, financial arrangements have been rejiggered, and those involved with the production can reap the rewards of an unexpected extension through July.

Which will likely include a Tony win in June. So far, “Bridge,” already a critical darling, is the sole contender for this year’s special-event award.