California Democrats sent shockwaves that will reverberate nationwide on Saturday when they issued a stunning blow to Democrat stalwart Sen. Dianne Feinstein.

In a move seen by many as a sign of the Democrat Party moving towards becoming more progressive, the California Democrat Party officially endorsed Sen. Feinstein’s opponent state Sen. Kevin de Leon in his bid to defeat the 85-year-old senator and take her spot in the United States Senate, Fox News reported.

And the vote was not close. State Sen. de Leon received 217 votes, around 65 percent, from the 360 members. Sen. Feinstein gained a total of 22 votes, near seven percent, and 94 votes, around 30 percent, were cast for no endorsement.

State Sen. De Leon is more progressive than Sen. Feinstein, and wrote the legislation to make California a sanctuary state.

The move came a month after Democrat Socialist Alexandria Ocasio-Cortez stunned entrenched NY Rep. Joe Crowley by defeating him the state’s Democrat primary.

As Fox News noted, the Party activists are generally more progressive than the state’s Democrats and Sen. Feinstein won the June 5 primary with 44 percent of the vote, making it unlikely that de Leon could defeat her.

“We are confident that a large majority of California Democrats will vote to reelect Sen. Feinstein in November,” Sen. Feinstein’s campaign manager, Jeff Millman, said.

But because California uses a top-two primary system it means that de Leon could defeat the Republicans running to face Sen. Feinstein, which could position him to take her on the in the race and have the two Democrats face off for a spot in the Senate.

In a statement from six Democrat House candidates there was a call for unity. “A divisive party endorsement for U.S. Senate would hurt all down-ballot candidates and our ability to turn out Democrats we desperately need to vote in November,” it read.

It is still a longshot for de Leon to defeat Sen. Feinstein, but the official endorsement, which the Party declined to give him in February, means that the California Democrat Party will spend funds to promote de Leon’s candidacy.