The Democratic senators will chair two key panels on the Senate's powerful Judiciary Committee.
She vacates her Assembly seat to be the new secretary of state, replacing Alex Padilla, who last week became the first Latino U.S. senator for California.
On Martin Luther King Jr. Day, Gov. Gavin Newsom also appointed Shirley Weber to be secretary of state, set to be the first Black person in the role for California.
California Gov. Gavin Newsom will appoint Democrat Alex Padilla to fill the vacancy.
Rep. Joaquin Castro and Sen.-designate Alex Padilla want immigrants working on the front lines of COVID-19 to get the chance to become U.S. citizens.
Padilla, who is California's secretary of state, will replace Vice President-elect Kamala Harris. He stands to become the state's first Latino senator.
The California secretary of state has emerged as the front-runner to replace Vice President-elect Harris in the Senate.
California Gov. Gavin Newsom (D) is under pressure to appoint either a Black woman, a Latino or a member of the LGBTQ community.
It's the result of major efforts in the state to increase youth civic engagement.
State election officials didn't know whether their systems had been targeted until Friday.