With primary voters going to the polls in 22 states on this Super Tuesday, a wave of artists as disparate as the Grateful Dead, Will.I.Am, OK Go and members of Pearl Jam are rallying support for Democ

With primary voters going to the polls in 22 states on this Super Tuesday (Feb. 5), a wave of artists as disparate as the Grateful Dead, Will.I.Am, OK Go and members of Pearl Jam are rallying support for Democratic presidential nominee Barack Obama.

On Monday (Feb. 4), the Grateful Dead reconvened for the first time since 2004 at San Francisco's 2,400-capacity Warfield Theater for Dead Heads for Obama, a concert that sold out within minutes of going on sale on Feb. 1.

Surviving Dead members Phil Lesh, Mickey Hart and Bob Weir took the stage for an 18-song set following a video message from Obama taped specifically for the event. Iclips.net had a streaming video feed of the event while Sirius Satellite Radio carried the audio on the dedicated Grateful Dead Channel.

There are over 400 Democrat delegates at stake in California, one of the states holding a primary today.

In New York, where nearly 300 Democrat delegates will be allotted, OK Go and a reunited Shudder To Think led a Barack Rock show aimed at getting younger voters to the polls. The Bowery Ballroom concert also included sets by Joan As Police Woman, countrified Brit rockers Alberta Cross, comedians Michael Ian Black, Michael Showalter and David Wain (performing as Stella), plus a brief guest appearance by "Knocked Up" actor Paul Rudd.

On Sunday night, Stevie Wonder performed briefly at an Obama campaign stop at UCLA.

In the realm of recorded endorsements, Black Eyed Peas' Will.I.Am gathered Common, Herbie Hancock, John Legend, Scarlett Johansson and others for "Yes We Can," a song and video inspired by and set to a Barack Obama stump speech. Directed by Jesse Dylan (son of folkie father Bob) features a split-screen of the celebrities speak-singing the chorus "yes we can" side-by-side with clips Obama saying the same phrase during a recent speech.

Pearl Jam's Stone Gossard, Jeff Ament, Mike McCready and Matt Cameron, meanwhile, posted "Rock Around Barack" to PearlJam.com. The song, a retooling of the 50's rock classic "Rock Around the Clock," comes days after the site posted a clip of Cameron playing drums on the Obama-inspired track "Fired Up and Ready to Go!" by Seattle's Bergevin Brothers and the Total Experience Gospel Choir.

Electronica artist Daedelus' side project FMB joined the chorus of support for Obama, releasing a song called "Obama" yesterday. Instead of a musical tribute, rapper Q-Tip issued a press release that said, in part, "I am endorsing Barack Obama because I feel that we can benefit greatly from a leader that offers sound judgment and experience rooted in the lives of real people."

Leah Kauffman contributed to this report.