By Cecilia Vega and Eric Johnson

A handful of A-list stars have taken center stage at the Democratic National Convention. Mary J. Blige, Marc Anthony and Foo Fighters performed, and even Scarlett Johansson made an appearance.

But there is one celebrity who has been working for the Obama campaign behind the scenes.

Cassidy Podell, known as DJ Cassidy, is a sought-after celebrity spin master, so much so that Beyonce and Kim Kardashian booked him to play at their weddings, and he has been known to rake in $100,000 for a single gig.

DJ Cassidy with Kim Kardashian on her wedding day, Aug. 20, 2011. Credit: Courtesy DJ Cassidy

While most delegates have probably never heard of him, DJ Cassidy is jamming his way through the DNC, hoping a little Madonna, Michael Jackson, Journey and Fleetwood Mac might bring some cool into the cold convention hall.

"It's about the feeling, the emotion. That's what I do in general, bring emotion to a room," he said. "We're all here to learn and to celebrate, and it's a fight for the future. That's how the songs make you feel."

A native New Yorker, Cassidy started DJ'ing at age 10. By the time he was 18, he said he was partying with models and spinning for P. Diddy. A global force, he has had gigs from South Africa to St. Barts.

President Obama first hired DJ Cassidy back in 2009 to play at the mid-Atlantic inaugural ball. Since then, DJ Cassidy has spun for the president's 50th birthday bash, a White House dance party, as well as at a Gen44 reception for Obama's 51st birthday in Chicago this year.

Credit: Courtesy DJ Cassidy

DJ Cassidy, who is easily recognizable by his trademark top hat and gold microphone, said he works with the Obama campaign to choose the perfect songs, and for the president, he said Stevie Wonder is always a good choice.

He added that he "didn't think much" of the Republican National Convention's playlist.

While DJ Cassidy refused to reveal songs from tonight's DNC playlist, he said he puts the great thought and consideration into the tunes President Obama walks out on stage to.

"The president is the main act here," he said. "Everything about that is the main attraction for everyone."

But for Cassidy, the goal is to keep the party going all the way until Nov. 6.

Tune into "Nightline" tonight at 11:35 p.m. ET at "Nightline" goes behind the scenes with DJ Cassidy at star-studded convention after-parties with Will.i.am and Eva Longoria.