Sen. Feinstein was the oldest member of Congress.
“Her passing is a great loss for so many, from those who loved and cared for her to the people of California that she dedicated her life to serving,” James Sauls, the chief of staff, said in a statement.
“She left a legacy that is undeniable and extraordinary. There is much to say about who she was and what she did, but for now, we are going to grieve the passing of our beloved boss, mentor and friend,” Mr. Sauls added.
Ms. Feinstein became a U.S. senator in 1992. She was reelected five times. Before her time in Washington, she was San Francisco’s mayor and a member of the city’s Board of Supervisors.
Ms. Feinstein’s latest husband, Richard Blum, died in 2022.
Ms. Feinstein had been struggling with health issues. She was briefly hospitalized in August after a fall. She was cared for in a hospital for months after contracting shingles in March. Complications from the infection included Ramsay Hunt Syndrome, which can cause facial paralysis. When she returned to the Senate, she was being pushed around in a wheelchair.
Ms. Feinstein had handed over power of attorney to her daughter as part of a battle over Mr. Blum’s estate.
Seat to be Filled by Governor
The seat held by Ms. Feinstein will be temporarily filled by a person chosen by California Gov. Gavin Newsom, a Democrat.
Under the U.S. Constitution, states have the power to fill vacancies that arise in the Senate.
Mr. Newsom has not said when he will make his choice. In a statement on Friday, he said Ms. Feinstein was “a dear friend, a lifelong mentor, and a role model not only for me, but to my wife and daughters for what a powerful, effective leader looks like.”
Ms. Feinstein’s seat was already set to become vacant in early 2025, as she had opted not to run for another term.
The race for the seat includes U.S. Reps. Barbara Lee (D-Calif.), Katie Porter (D-Calif.), and Adam Schiff (D-Calif.). Republicans running include attorney Eric Early and businesswoman Sarah Sun Liew.
