How Vice President-elect Kamala Harris' California US Senate seat will be filled and who could replace her

• Now President-elect Joe Biden and Vice-president elect Sen. Kamala Harris have won the Electoral College with a victory in Pennsylvania, Insider and Decision Desk HQ project.
• With Harris set to resign from her California US Senate seat for the White House, Gov. Gavin Newsom will appoint a replacement to serve out the rest of her time until 2022.
• Regardless of who Newsom appoints, California's deep bench of Democratic talent means the battle for Harris' seat in 2022 will be fierce.

Now President-elect Joe Biden and Vice-president Kamala Harris won Pennsylvania's 20 Electoral College votes on Friday, and with them, the United States presidency, Insider and Decision Desk HQ project.

And with Harris officially headed to the White House, California Democrats will soon begin jockeying for her soon-to-be-vacant US Senate seat.

Harris, a former California attorney general and San Francisco district attorney, was elected to a six-year term to the US Senate in 2016 to replace retiring Democratic Sen. Barbara Boxer. She will now make history as the first Black woman and first Asian American woman to run on a major-party presidential ticket.

Harris wasn't up for reelection this year, so she had the option to stay in her US Senate seat in case she and Biden lost. Virginia Sen. Tim Kaine, who was Hillary Clinton's 2016 running mate, lost the presidential race but stayed in his Senate seat and was reelected to the Senate in 2018.

When Harris resigns, Gov. Gavin Newsom will appoint someone to serve out the rest of her term until 2022, at which point there will be an election to fill her seat, per California Elections Code § 10720.

California is one of 37 US states in which governors fill a US Senate vacancy by appointment, while 13 states require a special election to fill a Senate vacancy, according to the National Council of State Legislatures. Five states, not including California, require the governor to appoint a person of the same party.

Newsom could appoint one of California's many rising political stars, or pick a retired politician without future ambitions to serve as a "caretaker" of the seat until 2022, if he wishes to be particularly cautious about not appearing to tip the scales.

Regardless of who Newsom appoints, California's deep bench of Democratic talent means the battle for Harris' seat in 2022 would be fierce.

California uses a jungle, or "top-two," primary system in which candidates of all parties run on the same primary ballot and the top two advance to the general, resulting in many elections between two Democrats.

Here's a nonexhaustive list of some of the top California Democrats who could be appointed to replace Harris:

• Former Sen. Barbara Boxer
• Former Gov. Jerry Brown
• Lt. Gov. Eleni Kounalakis
• Attorney General Xavier Becerra
• Secretary of State Alex Padilla
• Los Angeles Mayor Eric Garcetti
• San Francisco Mayor London Breed
• US House Rep. Eric Swalwell of the 15th Congressional District
• Rep. Adam Schiff of the 28th Congressional District
• Rep. Linda Sánchez of the 38th Congressional District
• Rep. Karen Bass of the 37th Congressional District
• Rep. Nanette Barragán of the 44th Congressional District
• Rep. Katie Porter of the 45th Congressional District
• Former California Senate President pro Tempore Kevin de Léon