Facing elimination, Bernie Sanders has vowed to win primaries in California and beyond even as Hillary Clinton secured the commitments of enough delegates to become the presumptive Democratic presidential nominee.
Campaigning in San Francisco, Sanders declined to speculate to reporters about what a poor showing in Tuesday's primaries might mean to his presidential campaign.
"Let me just talk to you after the primary here in California where we hope to win. Let's assess where we are after tomorrow," he said.
Hours later, at an evening rally at Crissy Field in the Presidio, Sanders steered clear of reports from The Associated Press and multiple television networks that Clinton had reached the 2383 delegates needed to become the presumptive Democratic nominee. She has 1812 pledged delegates won in primaries and caucuses, and the support of 571 superdelegates.
Sanders spokesman Michael Briggs said Clinton's support was dependent upon superdelegates who could still change their minds between now and the July convention.
He said the campaign's job is to convince the superdelegates that the Vermont senator is "by far the strongest candidate against Donald Trump".
He said calling the Democratic contest before superdelegates formally vote at the convention was a "rush to judgment".
Sanders' supporters expressed disappointment that the calls were made before California's primary and urged the senator to continue on despite the pronouncements.
"We're going to keep fighting until the last vote is counted," said Kristen Elliott, a Sanders' supporter from San Francisco who attended the rally.
Sanders and Clinton are competing in contests in six states on Tuesday, headlined by California, the nation's largest state, offering 475 pledged delegates. Clinton, a former New York senator, is heavily favoured in Tuesday's New Jersey primary and winning a share of the state's 142 pledged delegates would likely put her over the top.
Obama, who bested Clinton in 2008 during her first bid for the Democratic nomination, is preparing to formally endorse her and start aggressively making the case against Trump. AP k