California Democrats are losing faith in Hillary Clinton, according to a new Field Poll that shows her support plummeting in the Golden State — just as it has across the country — while voters here think it would be a “good thing” for Vice President Joe Biden to enter the presidential race.

Clinton’s 19-point decline since May — and 26-point drop since February — is coupled with a surge of support for her closest rival Bernie Sanders, the poll found.

Add it all up and California is now less of lock for Clinton than ever before. One thing that appears more clear is Democrats here are looking for something to get excited about.

“Certainly we’ve been hearing a lot from the Republican side, they’ve been having spirited debates,” said Field Poll Director Mark DiCamillo. “Maybe Democrats would like to see a little more attention paid to their side, and if Biden got in, that would add a little more balance and drama to the campaign.”

Sixty-three percent of Democratic likely voters said it would be a good thing if Biden runs, though only 15 percent said they would actually back him if he does.

With four months to go before the first-in-the-nation Iowa caucuses and eight before California voters weigh in, “it’s way too early to say” what will happen in the Golden State, DiCamillo said — especially given the upcoming Democratic debates, early primary results in other states, and whatever conclusion a federal investigation reaches on whether Clinton’s email practices jeopardized classified information.

If Clinton can effectively get people talking more about her issues than her emails, she has plenty of time to bounce back and widen her lead again, he said.

Whether it’s due to lingering questions about her private email server and ongoing House theatrics about the Benghazi attack, or it’s just the Golden State’s left-leaning predilections, only 47 percent of likely voters in next June’s Democratic primary now support the former U.S. senator and secretary of state. Sanders’ support has grown from 9 percent in May to 35 percent now; perhaps unsurprisingly, the self-described socialist Vermont senator’s strongest support is in the uber-liberal Bay Area, at 38 percent to Clinton’s 45 percent.

California’s June 7 primary is late enough in the season that voters here might have little say in who gets either party’s nomination, and the state is almost certain to be carried by a Democrat in November.

Yet the Field Poll — which surveyed 391 Democratic likely voters from Sept. 17 to Oct. 4, with a five-percentage-point margin of error — seems to reflect the party’s ambivalence as its candidates prepare for their first televised debate, hosted by CNN next Tuesday in Las Vegas. Sanders and former Maryland Gov. Martin O’Malley have led criticisms of the Democratic National Committee for starting its debates so late in the year, and for scheduling only six of them — conditions they say favor a “coronation” for Clinton.

Beyond the Golden State, Sanders has closed the gap so that Clinton now leads by only 16 percentage points in an average of nine recent national polls compiled by Real Clear Politics. In Iowa, she leads Sanders by six points; in New Hampshire, Sanders leads Clinton by 11 points.

Despite wavering from some supporters, California remains a rich source of campaign cash for Clinton — she was in the Bay Area just last week to raise money in Saratoga, Belvedere, Orinda and San Francisco.

Clinton is still the most likely to win California’s primary and the nomination, said Jack Citrin, director of UC Berkeley’s Institute of Governmental Studies, if only because she stands a better chance against any Republican nominee. “It’s improbable to me that someone with Bernie Sanders’ background would be nominated, especially once people start thinking about what’s likely to happen in the general election.”

Citrin chalked the poll numbers up to Sanders’ ability to “appeal to passionate elements of the base” while Clinton’s email problems “cast a kind of shadow over her” whether or not there’s actually fire beneath the smoke.

Laurie Koester, of San Jose, told the Field Poll she backs the former first lady, with Biden as her second choice.

Clinton “communicates well with other countries … it isn’t just us, it’s the world, and we have to remember that,” said the 64-year-old children’s counselor. She also likes Clinton’s environmental views and her willingness to entertain other viewpoints, and said she has handled Republican attacks on her trustworthiness with grace and aplomb. Yet Biden’s experience could enrich the race’s dialogue, she said: “He can kind of show her the ropes.”

Robert Carlson, of Richmond, supports Sanders but said he would enthusiastically support Clinton if she’s the nominee.

“As a practical matter, she’s got the name recognition and is going to get the nomination,” said Carlson, 65, who owns a white-water rafting equipment company. But given his support of universal health care, free college education and a Wall Street transactions tax, “Sanders is by far the best other voice out there. I think I’m going to give him some money and vote for him.”

Carlson isn’t impressed by Biden, however. “He’s folksy, but so what?”

Josh Richman covers politics. Follow him at Twitter.com/Josh_Richman. Read the Political Blotter at IBAbuzz.com/politics.