Five years ago, California voters blessed their senior U.S. senator with a decisive vote of confidence, sending the then 85-year-old Dianne Feinstein back to the nation’s capital for the sixth time instead of a much younger fellow Democrat.

But a poll out Thursday suggests many of those voters now have buyer’s remorse. The Berkeley Institute of Governmental Studies poll found two out of three registered California voters surveyed say Feinstein, now 89, after missing months in the Senate this year due to shingles complications and reportedly suffering memory lapses, is “no longer fit to continue serving in the U.S. Senate.”

Even so, the poll found voters divided over whether Feinstein should remain in office. While the largest proportion, 42%, said Feinstein should resign from the Senate and allow Gov. Gavin Newsom to appoint a successor, 27% said she should continue serving and 31% were undecided.

“The poll clearly shows that while support for Senator Feinstein has waned considerably since 2018, there is no clear consensus about how the process should play out,” said IGS Co-Director G. Cristina Mora. “This will impact her ability to connect with voters and serve her constituents over the remainder of her term.”

Feinstein’s office had no comment on the poll Thursday morning.

The poll also found a wide-open race to succeed Feinstein when her term ends in 2025. Republican lawyer Eric Early held a narrow lead with 18%, but with Democrats enjoying a two-to-one party registration advantage in California over the GOP, they are expected to hold the seat.

Among Democrats, Rep. Katie Porter led with 17% followed by Rep. Adam Schiff at 14% and Rep. Barbara Lee at 9%. Campaign representatives for those candidates had no immediate response Thursday.

But 32% of California voters surveyed remained undecided on their next U.S. Senator, and 10% said they would choose someone else.

The poll is undoubtedly a blow to Feinstein, a Democratic icon catapulted from obscurity as a San Francisco supervisor into the mayor’s office in 1978 following the shocking assassinations of Mayor George Moscone and Supervisor Harvey Milk by a former supervisor.

The experience made her a leading voice among Democrats for gun restrictions — as mayor she had called for a handgun ban that prompted a failed recall attempt. After an unsuccessful bid for governor against Republican Sen. Pete Wilson in 1990, she won a race for his vacated Senate seat in 1992.

As a U.S. senator, Feinstein authored a nationwide ban on sales of military-style semiautomatic rifles and pistols and magazines that hold more than 10 rounds of ammunition, which she has called on Congress to renew since it expired in 2004.

Feinstein also pushed legislation that increased fuel efficiency in automobiles, protected the 7,500-acre Headwaters Forest old-growth redwoods, 7 million acres of California desert and 16,500 acres of San Francisco Bay wetlands. She oversaw a six-year review of the CIA’s interrogation program and worked with Republican Sen. John McCain outlawing its use of torture.

Feinstein in 2012 got more popular votes for her re-election than any senator in U.S. history. And in her fifth re-election bid in 2018 against Kevin de León, then a 51-year-old Democratic state senator and now a Los Angeles City Councilman, she beat him 54% to 46%.

But Thursday’s poll suggest voters are losing confidence in Feinstein. More than half of surveyed voters — 52% — now have an unfavorable opinion of Feinstein, up from 49% in October 2018 shortly before her last re-election.

The poll found that while fewer Republicans view Feinstein unfavorably, 78% now and 87% in 2018, among Democrats, 38% now view her unfavorably, up from 22% in 2018. Only 43% of Democrats now view her favorably, down from 75% when she last ran for re-election.

The poll was conducted by the Institute of Governmental Studies at the University of California-Berkeley with funding by the Los Angeles Times. It surveyed 7,465 California registered voters including 5,236 likely voters online in English and Spanish from May 17-22, 2023, shortly after Feinstein’s U.S. Senate return. It had a margin of error of plus or minus 2 percentage points for the overall sample and 2.5 points for the subsample.

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