Virginia Commonwealth University head basketball coach Shaka Smart (Steve Helber/Associated Press)

But the second biggest? Virginia Commonwealth University basketball coach Shaka Smart, who gained a national following after his team’s unexpected success the past couple years.

Former governor Tim Kaine, a U.S. Senate candidate who served as Democratic National Committee chairman, will also speak before the late afternoon event.

U.S. Sens. Jim Webb and Mark Warner, both Democrats, will not be in attendance. Warner said he will be on a long-scheduled family trip.

U.S. Rep. Bobby Scott (D-Va.) and Richmond Mayor Dwight Jones will be at VCU’s Siegel Center for the rally, which is expected to draw thousands. The event is open to the public.

“Virginians know the president has been getting the job done, from creating new jobs to keeping our nation safe, and I am looking forward to seeing thousands of his supporters gather here in Richmond this weekend showing their support,’’ Jones said in a statement.

Obama’s campaign announced that it would officially launch his reelection Saturday with a pair of rallies in Virginia and Ohio. Both events will take place at colleges and continue the president’s focus on young voters. First lady Michelle Obama will join him.

The event comes after presumed Republican presidential nominee Mitt Romney spent two days in the state, campaigning and raising money.