"I am truly honored and humbled that the voters of Assembly District 16 have selected me to represent them in Sacramento," Bauer-Kahan wrote in a Facebook post on Friday. "I am ready to roll up my sleeves and get to work for them and the issues important to our community."
The East Bay district, which stretches southeast from the Caldecott Tunnel to the Altamont Pass, is increasingly difficult territory for any Republican, as Democrats hold a 14 point advantage in voter registration.
Bauer-Kahan’s campaign sought to cast Baker’s party affiliation as out of sync with the district and touted Bauer-Kahan’s support from more liberal groups like the Sierra Club and Planned Parenthood.
"I’ve got labels you can trust,” Bauer-Kahan proclaimed in one ad.
The victory for Bauer-Kahan, an environmental attorney, adds to the Democratic supermajority in the state Legislature. The party has added two seats in the Senate and four seats in the Assembly, based on Associated Press race projections and candidate concessions.
Democrats are also poised to take another seat in Orange County, where incumbent Republican Assemblyman Matthew Harper is trailing. Incumbent Democrat Sabrina Cervantes has a slim lead in her Riverside district.
The flipping of the 16th District has been a goal for Democrats since 2014, when Baker won the seat formerly held by Democrat Joan Buchanan.
In the Legislature, Baker maintained a moderate voting record. In the most recent session, she supported Democratic priorities such as the extension of the state's cap-and-trade program to limit emissions, a $4 billion housing bond and increasing the state's renewable energy goals -- while seeking to distance herself from President Donald Trump.