The rematch between incumbent San Joaquin Valley Rep. TJ Cox and the congressman he barely defeated in 2018 is down to the wire again.

Former three-term Republican Rep. David Valadao of Hanford led Cox, a Fresno Democrat, by a little more than 3,000 votes as of late Thursday, according to the California secretary of state's office. Valadao led, 56,269 to 53,236, with mail-in and provisional ballots still being counted.

The contest is in the 21st Congressional District, which includes Kings County and portions of Fresno, Kern and Tulare counties.

"It was the last-called congressional race in the nation two years ago," said Ryan Jacobsen, the Fresno County Farm Bureau's chief executive officer. "The race will not be over until every vote is counted."

In 2018, Valadao led by about 4,400 votes on election night and soon declared victory after the Associated Press called the race in his favor. But after mail-in ballots trickled in throughout the month, Cox was determined to have won by 862 votes on Nov. 28, 2018.

"Seeing the numbers come in early made us feel good, but we learned" from two years ago, Valadao, a dairy farmer, told KFSN-TV in Fresno. "We're not going to take anything for granted and we're watching every ballot get counted. And making sure we're doing this as legit as possible."

Related:California's Costa to seek ag committee chairmanship

Financial controversies

As a congressman, Cox has been dogged by several financial controversies, including his failure in 2018 to disclose business interests and failure to timely pay wages owed to three employees of Constellation Mines, a company where Cox was a director until early 2019, according to the Fresno Bee.

Earlier this year, Cox voted against a bill that would require members of Congress to report tax liens after the Internal Revenue Service placed a series of liens on him amounting to nearly $200,000 from 2017-2020, according to local news reports.

For his part, Valadao has been embroiled in a lawsuit concerning a 2016 accident at his family dairy where an employee's hand was severed, according to the Visalia Times-Delta.

As votes are being counted, both candidates are trying to sound optimistic.

"We're going to wait until every vote is counted, every voice is heard and then we'll be satisfied with the result," Cox told KFSN-TV.