The decimation of the California GOP continues three weeks after Election Day as Democrat T.J. Cox overtook GOP Rep. David Valadao by 436 votes in the rural 21st District.

If Cox hangs on, California Democrats will have flipped seven districts in the 2018 midterms, pushing Democratic gains nationwide to 40 seats. Democrats would control 46 of California’s 53 House seats, their highest percentage of the delegation ever, including all of Orange County, the previously reliable red belly of the state GOP.

On Election Day, it looked like Valadao had escaped with a victory by roughly 4,000 votes in the district, where three-quarters of the population is Hispanic and Hillary Clinton outpaced President Donald Trump by 16 points in 2016.

Inside Elections with Nathan L. Gonzales had rated the race for the 21st District Likely Republican, making a Cox’s potential victory one of the biggest upsets of the cycle.

The Associated Press, which sets the standard for calling races across the journalism industry, had projected Valadao’s re-election to a fourth term on Election Day.

But it can often take weeks for officials to declare a winner in California elections with razor-thin margins as they tally thousands of mail-in ballots that trickle in long after in-person polling places have closed.

The AP retracted its call on Monday after Cox overtook Valadao in the running vote count.

Counties have until Dec. 7 to complete their vote-counting, so Valadao is not finished. But mail-in votes tend to favor Democrats in the Golden State.

“Every update has kept us on track to win,” Phillip Vander Klay, a Cox spokesman, told the Los Angeles Times. “We’re still on that track.”

Valadao’s campaign could not be reached for comment.

Cox did not attend new member orientation after it appeared in the days after the election that he would not surmount his Election Day deficit.

Some people who did attend orientation, on the other hand, will not be heading to Congress, including Democratic challenger Nate McMurray of New York’s 27th District, who lost to incumbent GOP Rep. Chris Collins, and Republican Young Kim of California’s 39th District, who lost to Democrat Gil Cisneros in the race for retiring GOP Ed Royce’s seat.

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