Hillary Clinton clinches Democratic presidential nomination
Hillary Clinton will become the first woman to top the presidential ticket of a major US political party, according to an Associated Press count.
The former secretary of state, New York senator and first lady, has reached the 2,383 delegates needed to become the presumptive Democratic nominee.
She had a decisive weekend victory in Puerto Rico and a burst of last-minute support from superdelegates, who are party officials and officeholders.
Many of them are eager to wrap up the contest amid polls showing her in a tightening race with presumptive Republican nominee Donald Trump.
Mrs Clinton has 1,812 pledged delegates won in primaries and caucuses. She also has the support of 571 superdelegates, according to the Associated Press count.
The AP surveyed all 714 superdelegates repeatedly in the past seven months, and only 95 remain publicly uncommitted.
While superdelegates will not formally cast their votes for Mrs Clinton until the party's July convention in Philadelphia, all those counted in her tally have unequivocally told the AP they will do so.
"We really need to bring a close to this primary process and get on to defeating Donald Trump," said Nancy Worley, a superdelegate who chairs Alabama's Democratic Party and provided one of the last endorsements to put Mrs Clinton over the top.
The victory arrived eight years after she conceded her first White House campaign to Barack Obama. Back then, she famously noted her inability to "shatter that highest, hardest glass ceiling".
Campaigning this time as the loyal successor to the nation's first black president, Mrs Clinton held off a surprisingly strong challenge from Vermont senator Bernie Sanders.
He mobilised millions with a fervently liberal message and his insurgent candidacy revealed a deep level of national frustration with politics-as-usual, even among Democrats who have controlled the White House since 2009.
Mrs Clinton had a muted reaction to her claim on the nomination as she campaigned in California.
She told a cheering crowd she was on the brink of a "historic, unprecedented moment," but said there was still work to be done in the six states to vote on Tuesday.
"We're going to fight hard for every single vote," she said at a rally in Long Beach.
Mrs Clinton's campaign had worried that reaching the 2,383 delegate commitments could depress turnout in Tuesday's elections and give Mr Sanders an edge.
Even a strong showing for Mr Sanders in California and elsewhere would probably still leave him well short in the delegate count, but it could give him more motivation to fight on to the Democratic convention in July.
"Our job from now until the convention is to convince those superdelegates that Bernie is by far the strongest candidate against Donald Trump," said Sanders spokesman Michael Briggs.
Later, Mrs Clinton was basking in the glow of celebrity friends at a fundraising concert in Los Angeles.
Speaking at a star-studded fundraising concert at Greek Theatre in Griffith Park, she urged people to vote in the California primary.
She is pledging to "come out of the primary even stronger to take on Donald Trump".
The sold-out concert line-up included John Legend, Christina Aguilera and Stevie Wonder.