In his relatively brief political career, Barack Obama has already achieved miracles. Still, nobody expected the candidate to wake the dead--which is exactly what happened last night at San Francisco's Warfield Theater. After a four-year hiatus that easily could have been permanent, the Grateful Dead reunited to play a benefit concert for the presidential contender.

The four-hour concert, held on the eve of the California primary and attended by a crowd of 2,400, kicked off with a video clip of Obama, who thanked the members of the band for their endorsement. The candidate made only a single faux pas. "I want everyone to sit down and enjoy the music," he said, prompting a roar from the crowd. Sit down? No way.

The Dead, who officially broke up in 1995 after the death of guitarist Jerry Garcia, started in with "Playing In The Band," then took a typically circuitous route through such staples as "Sugaree," "Throwing Stones," "Deal," and "Iko Iko." Guitarist Bob Weir, drummer Mickey Hart, and bassist Phil Lesh, all original members of the band, were joined by Jackie Greene, John Molo, Steve Molitz, Mark Karan and Barry Sless. The late Garcia was also there and not just in spirit: A small, shaggy-haired Garcia doll rested on recording equipment on the right hand of the stage.

Between sets, band members shared their thoughts on the Illinois senator and his campaign. "I haven't seen something like this since Robert Kennedy in 1968," said Lesh, speaking of watching Obama at a rally last fall. "This is the real deal." In fact, Dead fans could thank Brian Lesh, the bassist's 18-year-old son, for the impromptu reunion. After spending the last summer working on Obama's campaign, he convinced his father and the rest of the band to do the show.

"Every few generations a guy like [Obama] comes along," drummer Hart told Reuters at a news conference held hours before the concert. "It seems like desperate times and we're desperate people."

Famously apolitical, the Dead have never before given their collective endorsement to a candidate. But band members have supported personal causes: Weir played at President Bill Clinton's inauguration festivities and publicly supported John Kerry in the last election, while Lesh is active in numerous issues in Marin County.

For Deadheads who'd already decided who to vote for, the band's imprimatur was sweet. "They just happen to be backing the guy I'm backing," said Mike Shoun, 37, a San Francisco resident who claims to have seen 75 Dead shows. "It's a nice coincidence." Other voters, such as Irenie Schlesinger, 49, were still undecided. "I was voting for Edwards, " shrugged Schlesinger, who added that she had spent the last 12 years following RatDog, Bob Weir's band, around the world.

Announced on the Dead's official web site last Friday, the concert sold out in less than an hour. On Craigslist, frantic fans offered at least $1,000 for a ticket. Crowds gathered outside the Market Street theater long before the show, with Deadheads hawking wooden pipes and light sticks. Overhead, a stereo system played the Dead (what else?) while hopeful fans trawled the crowd, looking for a spare ticket. Most simply held one finger aloft. Others were more direct. "I'll give you $600 for a ticket," yelled one young man, his arm upright, a fistful of bills in his hand.

Inside, a few local celebrities were spotted. Larry Brilliant, executive director of Google.org, the firm's charity, sat next to Sixties activist Wavy Gravy, while NBA star Bill Walton wandered the dance floor.

With a median age of 40-plus, there were fewer tie dyes, and more gray hairs spotted in the crowd. But whatever your political leanings, the event was a joyous celebration. Fans took cell phone pictures, strangers shared joints and friends reminisced about past shows. James Cottle and John Kantor, both who looked to be in their early 40s, had last seen the Dead play at Shoreline in 1995. "What's impressive is [the Dead's] fundraising skills," said Cottle, a self-professed independent. "They can still raise money for a good cause."

Jolie Wiggins, 48, had been to a "decade" worth of shows with longtime friend Danica Rehmy, 46. "We haven't been excited about anything in a long time," said Wiggins, referring to the country's political malaise. But, no, Wiggins hadn't decided on a candidate. Noting the sometimes fractious relationships between Dead members, Rehmy said it was significant that band was "doing something united" with tonight's concert. And looking around at the legions of potential voters, she wondered why no one had tapped these fans. "Has anyone ever thought of Deadheads as a voting block?" she asked rhetorically.

They did last night.

And via the band's official web site, Dead.net, the concert's set list:

I. Playing in the Band Brown-Eyed Women, Mississippi Half-Step Uptown Toodeloo, New Minglewood Blues, Come Together

II. (Acoustic) Deep Elem Blues, Friend of the Devil, Deal, Ripple

III.China Cat Sunflower, The Wheel, The Other One, Sugaree, Eyes of the World, Throwin' Stones, Iko Iko, Playing reprise

Encore: U.S. Blues