Democrats have a supremely deep bench of possible successors, along with some dark horses. The 2016 race also will be a test for whether Republicans can regain a Senate seat in the Golden State, which has eluded them since 1992.
Here’s an updated look at some of the possibilities, broken down by party and the person’s candidacy status:
Attorney General Kamala Harris: Harris announced Jan. 13 that she was running. Harris has recently been making the rounds in Washington and building her national profile, perhaps indicating a greater interest in the U.S. Senate than a potential gubernatorial run. She could benefit from an expected Hillary Clinton presidential campaign in 2016.
Former Los Angeles Mayor Antonio Villaraigosa: The former Assembly Speaker said Saturday he is looking closely at running for the seat. He has a huge political base, and changing demographics could benefit a Latino candidate. But Villaraigosa has said he enjoys being a chief executive, suggesting he may hold off until the governorship opens up.
Rep. Adam Schiff: The Burbank Democrat, elected in 2000, “has been encouraged by many Californians” to run for Boxer’s seat, he said.. Schiff recently became the top Democrat on the House Intelligence Committee. Schiff has emerged as a widely quoted expert on foreign affairs, yet it’s unknown how well that would help him in an expensive statewide race.
Rep. Xavier Becerra: The Los Angeles Democrat said he is taking “a very close look” at running for the Senate. Becerra has climbed the ranks in the House, where he has served since 1993. But it unclear how he would match up against Villaraigosa, who defeated him by a large margin in the 2001 race for Los Angeles mayor.
Lt. Gov. Gavin Newsom: Newsom has the portfolio to compete for Boxer’s seat. But the former San Francisco mayor, who rose to prominence after legalizing gay marriage in the city in 2004, announced Jan. 12 that he will pass. He is viewed as likely to run for governor in 2018.
Climate change activist Tom Steyer: The billionaire hedge fund manager said Thursday that he will not run. Steyer spent $74 million, mostly unsuccessfully, trying to elect more environmentally friendly candidates in 2014. Will Steyer finally make his own run for office? He can afford it.
Secretary of State Alex Padilla: While he’s the only Latino currently holding a statewide office in California, Padilla’s jump to a Senate campaign would come awfully quickly after his recent election to California secretary of state.
Treasurer John Chiang: After nearly two decades in statewide politics, Chiang could have enough name recognition to make a run at Boxer’s seat. He is also one of the most visible Asian Americans in a state where the rapidly growing population segment is increasingly flexing its political power.
Insurance Commissioner Dave Jones: Like Chiang, Jones was just re-elected in 2014 and would have a free ride at a long-shot bid for Boxer’s seat. His career has shown he’s not afraid to take up liberal causes.
California Senate President Pro Tem Kevin de León: One of the most prominent Latinos in California politics, de León has only recently begun to lead the Senate.
Former Senate President Pro Tem Darrell Steinberg: Following a successful 14-year run in the state Legislature, Steinberg is looking for a re-entry into political office. Though well-respected, the Sacramentan’s influence may be confined to the Capitol bubble.
Former Rep. Ellen Tauscher: The East Bay Democrat served in Congress from 1997 to 2009, when she took a job in the Obama administration’s State Department. She recently opined on the potential interest in Boxer’s seat: “It’s going to look like the Oklahoma land rush.”
Former state GOP chairman Duff Sundheim has opened an exploratory committee for a possible Senate run.
Former state GOP chairman Tom del Becarro also is weighing a candidacy.
Assemblyman Rocky Chavez, R-Oceanside, is considering a run.
Former U.S. Secretary of State Condoleezza Rice: A dream candidate for California Republicans, who have been wanting her to run for something – anything – for years. They’ll have to keep waiting.
Former U.S. Senate candidate Carly Fiorina: The former Hewlett-Packard CEO suffered a bruising loss to Boxer in 2010, for which she still owes money. Recently, Fiorina has been floating her name for a possible presidential run in 2016 instead.
San Diego Mayor Kevin Faulconer: As mayor of the second-biggest city in California, Faulconer has a platform but no statewide profile. He would also have to weigh his run against a mayoral re-election bid in 2016.
Fresno Mayor Ashley Swearengin: Swearengin inspired immediate buzz when she announced her ultimately unsuccessful bid for state controller last year. She has yet to demonstrate she can raise real money, though.
Former Rep. Doug Ose: Though coming off a narrow loss to Rep. Ami Bera in 2014’s most expensive House race, businessman Ose has shown previous interest in running for the Senate.
Rep. Ed Royce: One of California’s most established Republican politicians, Royce would have to give up a safe House seat in Orange County and a powerful chairmanship in Congress’ new majority.
Former gubernatorial candidate Neel Kashkari: The former U.S. Treasury official and political newcomer touted his economic credentials during a massive loss to Gov. Jerry Brown in November.
Call The Bee’s Alexei Koseff, (916) 321-5236. Follow him on Twitter @akoseff.