As expected, veteran Senator Dianne Feinstein (D-CA), now the longest serving Democrat in the chamber since former Sen. Patrick Leahy (D-VT) has retired, announced Wednesday that she will not seek re-election to a sixth full term in office.

The Senator originally claimed the seat in a 1992 special election and won her first six-year term two years later. During her Senate career she has chaired the Rules and Intelligence Committees.

Sen. Feinstein joins Michigan Sen. Debbie Stabenow (D) in retiring from politics. Indiana Sen. Mike Braun (R) is not seeking re-election to the Senate in order to run for Governor.

A number of Senators still have not announced their 2024 intentions. Sens. Kyrsten Sinema (I-AZ), Tom Carper (D-DE), Ben Cardin (D-MD), Jon Tester (D-MT), Kevin Cramer (R-ND), Sheldon Whitehouse (D-RI), Marsha Blackburn (R-TN), Mitt Romney (R-UT), Bernie Sanders (I-VT), Joe Manchin (D-WV), and John Barrasso (R-WY) have yet to disclose their 2024 political plans.

From this group, Sens. Sinema, Cramer, Whitehouse, Blackburn, and Barrasso are expected to seek re-election. Retirement speculation surrounds Sens. Carper, Cardin, Tester, Romney, Sanders, and Manchin.

Sen. Feinstein, 89 years of age, was first elected to the San Francisco Board of Supervisors in 1969 and became Board President in 1978. Later that year, she succeeded then-Mayor George Moscone (D) after his tragic assassination. Mayor Feinstein would then win election to the city executive position and serve a total of nine years. She lost the 1988 Governor’s race to then-Sen. Pete Wilson (R) but rebounded to win the Senate seat four years later.

Sen. Feinstein leaves in her political wake what promises to be a hotly contested open seat Senate race but largely among Democrats. Under California’s all-party jungle primary, it is probable that a pair of Democrats will advance into the general election from the March 5, 2024 qualifying election. This means we will likely see a Golden State intra-party political battle for more than a year.

Two Democratic House members, Reps. Katie Porter (D-Irvine) and Adam Schiff (D-Burbank) had both declared their Senate candidacies weeks before the incumbent made public her own re-election decision. Now that Sen. Feinstein has announced her retirement, expect Rep. Barbara Lee (D-Oakland) to soon become a Senate candidate. Another Bay Area Congressman, Ro Khanna (D-Fremont/Santa Clara), is said to be considering the Senate race but reportedly will yield to Rep. Lee and instead seek re-election.

It is unlikely that we will see any statewide officials join the race, so a battle between House members seems the most probable scenario.

Among the congressional members vying to succeed Sen. Feinstein, Rep. Lee would seem to be at a clear disadvantage. She does not command the fundraising ability of both Reps. Porter and Schiff – the latter are the top two non-leadership fundraisers who each attracted more than $25 million to their 2022 re-election bids – and is a political unknown in populous southern California. Therefore, the early favorites to advance to an expensive general election battle are Reps. Porter and Schiff.

With Gov. Gavin Newsom (D) being term-limited in the 2026 election, several statewide officials, Lt. Gov. Eleni Kounalakis (D), Attorney General Rob Bonta (D), and state Treasurer Fiona Ma (D) are all potential gubernatorial candidates. AG Bonta has already said he will not run for the Senate next year. Lt. Gov. Kounalakis and Treasurer Ma are both term-limited in 2026, but not expected to seek the Senate seat. Therefore, building a gubernatorial campaign, at least for the two term-limited officials, seems to be the political priority.