Determining who is the Democratic nominee for state labor commissioner could take more than a month and cost taxpayers millions of dollars.

According to complete but unofficial returns, none of the four Democrats on Tuesday's primary ballot accumulated 40 percent of the vote, the minimum to avoid a runoff.

The eventual winner will face Republican incumbent Cherie Berry, who ran unopposed in the GOP primary.

The closeness of the results could set the stage for a statewide recount and a runoff election June 24 between the top two primary finishers.

Mary Fant Donnan, a former research director at the Labor Department, placed first with 28 percent of the vote.

The remaining three candidates -- former Labor Commissioner John Brooks, Raleigh labor lawyer Robin Anderson and Middlesex resident Ty Richardson -- are knotted at 24 percent.

Brooks has a 3,662-vote lead over Richardson, but an unknown number of absentee and provisional ballots remain to be counted.

Local boards of election across the state will meet Tuesday, one week after the primary, to certify the result.

Gary Bartlett, executive director of the State Board of Elections, said it is unlikely that enough ballots are outstanding to give any of the three a lead of more than 1 percent of the vote.

"They're crowded, that's for sure," Bartlett said.

Under state law, a candidate who loses by a margin of less than 1 percent can request a recount by noon Thursday, May 15. A statewide recount could take several days, Bartlett said.

May 15 is also the deadline for the second-place finisher to request a runoff.

Bartlett said a statewide runoff could cost about $4 million.

Brooks said he will wait until Tuesday, when the provisional and absentee ballots are counted, to decide whether to request a runoff.

"We'll just have to see what the situation is," he said.

Donnan said Wednesday that she looks forward to a runoff, if one is called for.

"I feel good about it," she said. "I feel like I've got a nice network around the state, and it's a good opportunity to get to know the state better."

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