SAN DIEGO — The offices of the San Diego Opera once filled the penthouse atop the Civic Center Plaza, with 12-foot ceilings and sweeping views of this city and its harbors. No more. These days, opera executives toil away in the decidedly less glamorous former offices of the public defender, with hallways stacked with boxes and unhung pictures lined against the walls.

“I now look at a parking lot,” said Keith A. Fisher, the opera’s chief operating officer, after coming downstairs in jeans and sneakers to escort a visitor up. “My, how things have changed.”

He sighed. “But it is a nice parking lot,” he said. “It’s good to shed some of our past.”

Five months ago, the opera company here appeared on the brink of extinction after its board of directors, responding to the dismal economic and attendance news confronting opera companies from New York to San Francisco, voted overwhelmingly to close down after 49 years.

But things did not work out that way. An unlikely coalition — opera buffs, labor unions, community leaders caught off guard by the threat of the company’s collapse and worried about the damage it would do to San Diego’s civic reputation — formed a rescue mission. Their efforts reversed the shutdown vote and rebuked the old guard, as the group’s members sought to prove that opera could still thrive not only here but also across the country. A fund-raising campaign that was kicked off in response to the vote to close the opera brought in $2.23 million, a sign of community support at a time when many old-line backers had drifted away. Now, in another hopeful sign, first-time subscribers are up 285 percent over last year.