Adam Lambert, the glam-rocker who rose to prominence on television’s “American Idol,” is the latest celebrity to be enlisted by the campaign to uphold Maryland’s same-sex marriage law.

Lambert has been booked next week for a benefit concert at the 9:30 Club in the District, with proceeds to go to Marylanders for Marriage Equality, the group leading the campaign for November’s ballot measure known as Question 6.

Singer-songwriter Adam Lambert poses during Spring 2013 Mercedes-Benz Fashion Week at Lincoln Center for the Performing Arts on Sept 11. (Andrew H. Walker/GETTY IMAGES FOR MERCEDES-BENZ FASHION WEEK)

“Marriage equality is about treating everyone as equals, regardless of who they fall in love with,” Lambert said in a statement. “I’m honored to appear at this event to help do whatever I can to bring notice to a cause that is close to my heart.”

Both sides are gearing up for the final crucial weeks that will determine whether voters retain a law signed by Gov. Martin O’Malley (D) in March to allow gay nuptials in the state. Opponents of the measure promptly petitioned it to the state ballot.

Organizers of the Lambert benefit said it grew out of a request from O’Malley and Montgomery County Council President Roger Berliner (D-Potomac-Bethesda) to Seth Hurwitz, a lifelong Marylander and chairman of I.M.P., co-owner of the 9:30 Club.

“Although we historically don’t get involved in political causes, on this issue I cannot stand by,” Hurwitz said.

Tickets to the fundraiser, which start at $125, go on sale Friday.