While this year’s abnormally cold November may be coming to a close, the last contested midterm race is still heating up in California.

The Associated Press, which had previously called the race for California’s 21st Congressional District in favor of incumbent Representative David Valadao (R), retracted its statement Monday as new ballot data came in giving his Democratic opponent the lead.

“The AP had declared Republican David Valadao the winner. However, Democrat T.J. Cox has taken the lead in the vote count,” the AP said in a tweet. “No new call will be made until the results are certified.”

The Fresno Bee reported Monday that although election officials still have thousands of ballots yet to count, Cox had taken a 438 vote lead over Valadao. The report marks Cox’s first lead in the race against the popular Republican incumbent.

“With today’s updated vote count, we now lead by 438 votes,” Cox tweeted Monday. “There are still many votes to be counted and each voter deserves to have their voice heard. I’m incredibly grateful and humbled by your support.”

Should he win the hotly contested race, Cox would become the 40th Democrat to flip a Republican controlled seat in the House.

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