According to event promoter Free Association SF, about 400 people showed up to dance and chat at the first "Bern Baby Bern" party in December.
"This energy is the reason that Bernie continues to surge in all the polls," organizers wrote on the event's Facebook page.
The idea for a disco party is a tribute to Sanders dancing to The Trammps' 1976 anthem "Disco Inferno" during an October appearance on "The Ellen DeGeneres Show."
While the event is free and not an official fundraiser for Sanders, patrons are encouraged to donate directly to the Democratic presidential hopeful's campaign.
Guests must be 21 and older.