California Democratic Party leaders took a step to the left Saturday night, endorsing liberal state lawmaker Kevin de León for Senate in a stinging rebuke of Democratic Sen. Dianne Feinstein.

De León's victory reflected the increasing strength of the state party's liberal activist core, which was energized by the election of Republican Donald Trump as president.

The endorsement was an embarrassment for Feinstein, who is running for a fifth full term, and indicates that Democratic activists in California have soured on her reputation for pragmatism and deference to bipartisanship as Trump and a Republican-led Congress are attacking Democratic priorities on immigration, healthcare and environmental protections.

De León, a former state Senate leader from Los Angeles, received 65% of the vote of about 330 members of the state party's executive board — more than the 60% needed to secure the endorsement. Feinstein, who pleaded with party leaders meeting in Oakland this weekend not to endorse any candidate, received 7%, and 28% voted for "no endorsement."