The speech, at an airport hangar in Santa Monica, Calif. on Tuesday, came hours after Hillary Clinton, the presumptive Democratic nominee, gave a soaring victory speech at her campaign headquarters in Brooklyn and turned her attention to the general election.
Facing a 22-point deficit in California with a third of the vote counted, Mr. Sanders took the stage amid speculation that he might drop out of the race and throw his support behind Mrs. Clinton. However, he stuck closely to his stump speech, railing against income inequality and the corrupting influence of money in politics while attempting to lift the spirits of his supporters.
“You all know it’s more than Bernie, it is all of us,” he said, the New York Times reported.
Mr. Sanders said that he had a “gracious” telephone conversation with Mrs. Clinton on Tuesday evening. He plans to travel home to Vermont on Wednesday and then on Thursday to Washington, D.C., where he will hold a rally and meet with President Obama.
Despite the fact that Mrs. Clinton has secured the majority of the pledged delegates, superdelegates and a larger portion of the popular vote, Mr. Sanders still insisted that he would continue fighting until the Democratic convention in Philadelphia in July.
His campaign has been actively trying to get superdelegates to abandon Mrs. Clinton in favor of him based on the argument that polls show him as a stronger candidate to face Donald J. Trump, the presumptive Republican nominee.
“We are going to fight hard to win the primary in Washington, D.C., and then we take our fight for social, economic and racial justice to Philadelphia,” Mr. Sanders said.