Clooney and Roberts also will be featured in posts and messages to supporters.
The fundraiser would be the latest big scale event lending celebrity and political star power to Bidens campaign.
The latter event raised $26 million, according to the campaign.
Julia Roberts and George ClooneyPhoto by Pascal Le Segretain/Getty Images
Axios first reported on the latest event; NBC News on the contest.
Tickets start at $2,500 per person and rise to $25,000 for the host level.
