For those in the right place at the right time, there are plenty of star sightings to be had while the Democratic National Convention is in Denver.

John Legend was the most visible of the entertainers who flowed into town, performing his new song "If You're Out There," from the floor of the convention at the Pepsi Center Monday.

Among other celebrities spotted on the first day of the convention were Will Smith, Danny Glover, Kal Penn, Tim Daly, Anne Hathaway, Ellen Burstyn, Josh Lucas and Susan Sarandon.

At a Rock the Vote concert Monday night, Pete Wentz of Fall Out Boy told the crowd that his parents met while working for Democratic candidate Sen. Barack Obama's running mate, Sen. Joe Biden.

Wentz said that his father told him to remind Biden of that if he ran into the vice presidential candidate.

The rocker told his dad, "Uh, that's not really how this works."

Several famous faces turned up in Denver as early as Sunday. Among them were singer Carly Simon, filmmakers Spike Lee and Tony Goldwyn and several actors, including Dana Delaney, Alan Cumming, Matthew Modine and Daryl Hannah.

Singers Sheryl Crow, Dave Matthews and Sugarland's Jennifer Nettles staged a DNC kickoff concert at the Red Rocks Amphitheater outside of Denver Sunday night, one of many slated for this week at various venues around the city.

On Tuesday, performers at various venues include Everclear, Daughtry and Moby. Folk legends James Taylor, David Crosby and Graham Nash will also be in Colorado Tuesday, playing at a Boulder-based radio station.

Several A-list stars are scheduled to be in Denver Wednesday to either perform or simply lend support.

Jennifer Lopez is set to present an honor at the Denver Art Museum while her ex-fiance, Ben Affleck, will be promoting "America's Second Harvest" foodbank. In addition, the Black-Eyed Peas will be staging a concert at Denver's Fillmore Auditorium, while Kanye West will be performing a concert sponsored by the activist organization ONE and the Recording Industry Association of America.

Though not confirmed, other celebrities expected to turn up in Denver include Warren Beatty and Annette Bening, Charlize Theron, Forest Whitaker and Edward Norton. Also expected is Josh Brolin, who plays President George W. Bush in Oliver Stone's upcoming film "W."

Without question, Obama's biggest celebrity supporter is talk show mogul Oprah Winfrey, who will be at Denver's Invesco Field Thursday for Obama's acceptance speech.

Not all celebrities coming to Denver appear to be Obama supporters. On Wednesday, actors Sean Penn and Val Kilmer are schedule to speak at a rally for independent candidate Ralph Nader.