Virginia's governor is facing mounting pressure to resign after a racist photo from his medical school yearbook surfaced on Friday.

Democratic Gov. Ralph Northam has apologized for the photo that appeared in his 1984 yearbook, which shows one person in blackface alongside another wearing a Ku Klux Klan hood and robe.

On Friday, Northam issued a statement saying he was "sorry for the decision I made to appear as I did in this photo," but on Saturday, a Virginia Democrat who spoke with Northam told the Associated Press that the governor now does not believe he was in the picture and has no plans to resign.

But the calls for Northam to step down came swiftly Friday, including from several of New Jersey's elected leaders.

Democratic Gov. Phil Murphy said in an MSNBC appearance Friday that Northam should resign. "Unacceptable in 2019, and it was just as unacceptable in 1984," Murphy said of the photo. "I don't think the governor's got any other choice other than to step aside... I say with a heavy heart because I know him and I think he's a good man."

And New Jersey Democratic Sen. Cory Booker capped his first day as a presidential candidate with a rebuke of Northam. "We should expect more from our elected officials. He should resign," Booker said.

Vermont Sen. Bernie Sanders and former Vice President Joe Biden also said Northam should resign immediately. They join a cascade of officials from both parties in Virginia and across the country demanding that Northam step down.

A protest was held Saturday morning in Virginia's capital of Richmond -- the former capital of the Confederacy.