Willie Nelson will headline a rally for Senate candidate Beto O’Rourke on at Auditorium Shores on September 29. Tamir Kalifa for American-Statesman 2016

After bringing Beto O’Rourke onstage during his Fourth of July Picnic this summer, Willie Nelson is doubling down on his support of the U.S. Senate candidate, headlining a rally and concert set for Sept. 29 at Auditorium Shores. And he’s bringing some heavy-hitter support, including Fort Worth soul star Leon Bridges.

Also on the bill are Joe Ely, Carrie Rodriguez and Tameca Jones. Admission is free but requires an RSVP via O’Rourke’s website.

A press release from Nelson’s publicist describes the event as “the first public concert Nelson has held for a political candidate.”

“ My wife Annie and I have met and spoken with Beto and we share his concern for the direction things are headed,” Nelson said in the press release. “Beto embodies what is special about Texas, an energy and an integrity that is completely genuine .”

Nelson’s new album “My Way,” featuring standards associated with the repertoire of Frank Sinatra, comes out Friday on Legacy Recordings.

RELATED: More Willie Nelson news on Austin360

Will Beto jam with Willie again? That’s what happened during the encore of the July Fourth Picnic, when O’Rourke joined in on acoustic guitar for the finale of “Will the Circle Be Unbroken” and “I’ll Fly Away.”

So @BetoORourke not only stuck around to sing with @WillieNelson, he played guitar with him. pic.twitter.com/HZdod0WLqr

— Peter Blackstock (@Blackstock360) July 5, 2018