CALIFORNIA — USC and KABC-TV Los Angeles canceled a California gubernatorial debate hours before it was scheduled to occur after criticism that only white candidates had qualified. The debate organizers invited Democrats Katie Porter, Tom Steyer, and Eric Swalwell; Republicans Chad Bianco and Steve Hilton; and Matt Mahan based on polling and fundraising criteria.

All six invited debate participants were white. The criteria excluded Xavier Becerra, Antonio Villaraigosa, Tony Thurmond, and Betty Yee, who are nonwhite.

"Concerns about the selection criteria for the debate have created a distraction from the issues that matter to voters." USC said in a statement late Monday night. "Unfortunately, USC and KABC have not been able to reach an agreement on expanding the number of candidates at tomorrow's debate. As a result, USC has made the difficult decision to cancel tomorrow's debate and will look for other opportunities to educate voters on the candidates and issues."

The campaigns of the excluded candidates held a Friday evening news conference calling on all invited participants to skip the debate. "We ask each and every candidate who is in this race to recognize that if we can't have a fair process for a debate, then we should all not participate. We call on them to withdraw from this biased forum." said Xavier Becerra, former Health and Human Services Secretary.

The Mahan and Steyer campaigns were working to hold an alternative event later Tuesday that would include both the original invited participants and the excluded candidates, but plans had not been finalized, according to Tasha Dean, Mahan campaign spokesperson. Tom Steyer said his team had secured a venue in Los Angeles and was reaching out to invite all major candidates, including Republicans.

The Democratic candidates for California governor include Rep. Eric Swalwell, former Rep. Katie Porter, former Health and Human Services Secretary Xavier Becerra, former Los Angeles Mayor Antonio Villaraigosa, billionaire activist Tom Steyer, state Superintendent of Public Instruction Tony Thurmond, former state Controller Betty Yee, and San Jose Mayor Matt Mahan.

At least ten Republicans are running for California governor, including Riverside County Sheriff Chad Bianco and Steve Hilton. In California's gubernatorial primary, candidates from all parties appear on the same ballot, and the top two vote-getters advance to the November election.