The California Democratic Party has endorsed state Sen. Kevin de León over Sen. Dianne Feinstein, backing a challenger who is taking on a longtime incumbent.

The endorsement came after Feinstein had encouraged party leaders not to endorse either candidate for Senate in the name of party unity. But on Saturday, de León won 65 percent of the delegates’ votes, surpassing the 60 percent threshold necessary to secure the endorsement.

“Earning the endorsement of so many leaders and activists of the @CA_Dem party isn’t just an honor and a privilege; today’s vote is a clear-eyed rejection of politics as usual in Washington, D.C.,” de León tweeted Saturday.

The intraparty battle has become a microcosm for the fight over the soul of the Democratic Party, with some pushing the party further to the left. De León has argued that he is more liberal and more willing to fight against President Donald Trump. Feinstein has countered that she is well-equipped to take on the Trump administration, thanks in part to her seniority in the Senate,  which gives her significant influence over policymaking and oversight activities.

The all-Democratic general election is a product of the Golden State’s unique primary system. De León finished second to Feinstein in the state’s top-two primary on June 5, where candidates from all parties compete on one ballot and the top two vote-getters advance to November.

Neither candidate won the party’s endorsement before the primary, but candidates also compete for a post-primary endorsement. State leaders met over the weekend to weigh endorsing a number of candidates, which can be particularly contentious in races featuring two Democrats.

Sixty-five percent of delegates, or 217, voted to endorse de León compared to 7 percent, or 22, who backed Feinstein. Twenty-eight percent, or 94 delegates, opted not to endorse either candidate.

Feinstein’s team wasn’t sweating the party’s decision.

She handily won the June 5 primary, winning 44 percent, or 2.9 million votes, in a crowded field. De León trailed with 12 percent, or 804,000 votes. While the primary included voters from all parties, Feinstein’s campaign noted that she did particularly well among Democrats.

“While 217 delegates expressed their view on Saturday, Senator Feinstein won by 2.1 million votes and earned 70 percent of the Democratic vote in the California Primary election, carrying every county by double digits over her opponent,” her campaign manager Jeff Millman said in a statement. “We are confident that a large majority of California Democrats will vote to reelect Senator Feinstein in November.”

Still, Saturday’s endorsement could connect de León to party resources and help him stay competitive with Feinstein. The four-term senator had $7 million in her campaign at the end of the pre-primary reporting period on May 16, while de León had $694,00 in the bank.

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