Tim Keller, the mayor of this city of 560,000 still struggling to emerge from a long economic slump, left some in the audience with jaws agape when he shouted above the shredding of Scott Ian, the Anthrax guitarist, “I believe in the power of metal!”

Mr. Keller, 40, a Democrat who took office in December, is making his enthusiastic embrace of heavy metal a signature feature of his administration, introducing metal bands onstage at gritty downtown venues, publicly extolling the music of his favorite band, Sepultura of Brazil, even fondly reminiscing about how he once got booted from an Ozzy Osbourne concert after jumping off a wall and into the audience at Tingley Coliseum.

“Albuquerque has always been pretty strong on the heavy metal front,” Mr. Keller said in an interview over a hurried lunch of green chile stew at his office, with a view of the Sandia Mountains in the distance. “What can I say, this is something I’ve been into for a long time.”