It was a star-studded sing-a-long inside the Wells Fargo Center.
There was a celebrity sing-a-long at the DNC Wednesday as some of Hollywood’s biggest names came together to sing a rousing rendition of "What the World Needs Now."
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Idina Menzel, Darren Criss, Kristen Bell, Audra McDonald, Ben Vereen, Tyne Daly, Debra Messing, Richard Kind, Rosie Perez and others appeared together to sing the 1965 Jackie DeShannon tune.
Rocker Lenny Kravitz took a break from opening for Guns N' Roses and rocked the Wells Fargo Center with his 1989 hit "Let Love Rule."
He was thrilled to be at the convention and posted about the experience on Instagram.
Musicians also performed outside of the arena and around Philadelphia.
Fergie headlined a concert at The Electric Factory for The Creative Coalition, a social and public advocacy organization for entertainers.
Her band, Black Eyed Peas, performed at a separate concert at the same time inside The Fillmore. The group, who has been on hiatus since 2011, seems to be continuing without their frontwoman.