Atty. Gen. Kamala Harris will announce Tuesday that she is running for the U.S. Senate seat being vacated by Barbara Boxer, according to a Harris adviser.
"She's not testing the waters. She's charting the course. She's in with both feet," said the source, who requested anonymity to discuss Harris' plans.
The move comes as Lt. Gov. Gavin Newsom announced Monday that he would not run for the seat.
The announcements avert an ugly battle between the pair, who share many of the same supporters, have national profiles, are both from the Bay Area and are popular among the liberal wing of the Democratic Party.
Harris, 50, is a two-term attorney general who previously served as the district attorney of San Francisco. She is the first candidate to officially declare that she would mount a bid for the seat. Boxer announced last week that she would not seek reelection in 2016, setting off a mad scramble among Democratic politicians in California who have not seen an open U.S. Senate seat since 1992.
Former Los Angeles Mayor Antonio Villaraigosa and billionaire environmental activist Tom Steyer are seriously considering bids, as are several members of Congress. On the Republican side, Assemblyman Rocky Chavez and two former state GOP chairmen are weighing runs.
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