Kentucky's volatile Republican primary for governor ended in a virtual tie Tuesday night as less than 100 votes separated Matt Bevin and James Comer.

Republicans Hal Heiner and Will T. Scott conceded early, and it appeared Bevin was headed to an improbable victory following his lopsided loss to U.S. Sen. Mitch McConnell in last year's primary. But Comer surged ahead by a narrow margin following returns from the western part of the state, including large margins in Warren County, where Republican presidential candidate Rand Paul lives.

By the end of the night, Bevin led Comer by 83 votes. The Secretary of State's office was unsure how many ballots from the state's overseas voters, including soldiers, came in by the 6 p.m. deadline. The court ordered an extension on the deadline for another 11 days because of a problem with an outside vendor. But that extension applied only to 12 specific ballots.

There are no runoff elections in Kentucky and no automatic recounts. State law allows for recanvassing only if a county clerk or a county board of elections notices a discrepancy or if a candidate makes a written request to the Secretary of State.

Comer said late Tuesday that he would ask for a recanvass, which is essentially a review of the vote totals in each county. State law says a recanvass would happen on May 28.

"This has been a difficult election. We've gone through a lot together in this race," Comer told supporters at the Capital Plaza Hotel in Frankfort. "We overcame so much money, we overcame the bad press with the newspapers in the state. We overcame a lot. And I owe it to our supporters to ask for a recanvass."

Bevin's campaign manager, Ben Hartman, said they "have a very high confidence that the results as they stand currently will hold."

Bevin appeared to declare victory on Tuesday night, telling supporters that he had "terrific conversations" with Comer and Heiner. He highlighted his running mate Jenean Hampton, who if elected would become the state's first African-American to hold statewide office.

"We stand before you tonight as a team. We both grew up below the poverty level, but we have both been blessed to live the American dream," Bevin said. "We are Kentucky. We are black, white, male, female, we are Kentucky."

Whoever wins will have to unify a state Republican Party torn apart by the raucous primary. Comer called it "the dirtiest campaign that I've ever witnessed in Kentucky history." He spent the last two weeks fighting allegations from Marilyn Thomas, his former college girlfriend, that he emotionally and physically abused her while the two dated at Western Kentucky University more than two decades ago.

But Comer, the state's agriculture commissioner, forcefully denied the allegations and used them to paint Hal Heiner, one of his leading opponents, as a dirty campaigner willing to do anything to get elected.

As Comer and Heiner fought, that left Bevin, with the $5 million and name recognition he earned from his failed U.S. Senate bid the year before, as the landing spot for disaffected Republican voters. He ran a TV ad with actors portraying Comer and Heiner sitting at a children's table throwing food at each other.

Heiner conceded around 8:40 p.m., as votes in the western part of the state were still being tallied and Bevin was ahead. Heiner told a sullen-faced crowd of his supporters in a reception hall at the Parklands of Floyds Fork that he called Bevin, congratulated him and pledged his support in the general election.

Heiner did not mention Comer in his concession speech, but he urged Republicans to unite.

"While we are disappointed, I ask you to all stay involved. Support the Republican party," he said. "It is time to move forward. Kentucky needs you, it needs your enthusiasm, your passion for good government."

Comer told supporters in Frankfort that he called Bevin and asked for a recanvass.

"And I told Matt Bevin that if this recanvass doesn't work out, I will gladly stand with you, I will walk with you door to door and every house in this state to help get you elected in November," Comer said.

Bevin and Comer agree on most major policy issues, including passing laws to ban companies from forcing its employees to join a labor union and vowing to dismantle the state-run health insurance exchange authorized by the federal Affordable Care Act.

Democratic nominee Jack Conway characterized those policies as "harmful to the working families of Kentucky."