A defiant Bernie Sanders vowed to remain in the race for the Democratic presidential nomination despite a night of rough losses to Hillary Clinton, who has now secured enough delegates to become the presumptive nominee.

“We are going to fight hard to win the primary in Washington, D.C., and then we take our fight for social, economic, environmental justice to Philadelphia, Pennsylvania,” Sanders told supporters in Santa Monica, Calif., late Tuesday.

The Vermont senator took the stage surrounded by his family and relatives, initially giving the appearance he was about to concede the race.