In 2016, Harris became only the second Black woman ever elected to the U.S. Senate, after former Sen. Carol Moseley Braun, D-Ill., who served from 1993 to 1999.
As a former prosecutor, Harris also played a key role on the Senate Judiciary Committee.
Former San Francisco Mayor Willie Brown, who is Black, has urged Newsom to not only select a woman of color – but a Black woman specifically, according to Los Angeles-based ABC 7. The influential ex-mayor played roles in the early political careers of both Newsom and Harris, and openly discussed a past extramarital relationship with Harris.
"We've only, in the history of this nation, had two Black women in the U.S. Senate: Carol Moseley Braun and Kamala Harris," he told the station. "And to fill that with someone other than a Black woman, I think, would be inconsistent with really good judgment."
If Brown has his way, potential candidates for the job could be congresswomen Maxine Waters, Karen Bass, and Barbara Lee.
But leaders of California’s sizable Hispanic and Latin American communities also called on the governor to choose a candidate who shares their background, the San Francisco Chronicle reported.
Those could include Secretary of State Alex Padilla, a possible front-runner and a friend of Newsom’s who was previously an aide to California’s other senator, Sen. Dianne Feinstein; or Attorney General Xavier Becerra, according to the paper. Latinos make up about 40% of the state’s population.
For her part, Feinstein told Fox News last week the job should go to “a good Californian.”
Two Democratic lobbying groups called for Newsom to choose a woman of color for the seat in full-page ads published Monday in the San Francisco Chronicle and Los Angeles Times. They argued that the vice president-elect is one of just four senators who fits that description, and “women of color are the core drivers of electoral progress in this country.”
The letter was signed by more than 150 Democratic female donors, according to the papers.
Harris will vacate her Senate seat to become the first woman of any race to serve as vice president. Before joining the Senate, she served as a district attorney in San Francisco and later as California’s attorney general.
Other potential replacements could include House Intelligence Committee Chairman Adam Schiff, Reps. Katie Porter and Ro Khanna, former Rep. Katie Hill, Long Beach Mayor Robert Garcia and Los Angeles Mayor Eric Garcetti. And it’s possible Newsom could appoint himself.
At a news conference Monday, Newsom said he had not picked a replacement for Harris but planned to do so before Inauguration Day.
Fox News’ Chad Pergram contributed to this report.