COLUMBIA - A day after the primary, Henry McMaster's opponent in the runoff to determine the GOP lieutenant governor nominee remains unclear.

The second-place finisher in the four-way Republican race likely won't be official until at least Saturday.

Unofficial results of Tuesday's primary show less than 1 percentage point separating retired Kiawah Island developer Pat McKinney and Mike Campbell, son of the late Gov. Carroll Campbell. Both received about 24 percent of the vote, with McKinney slightly leading.

County officials will rule on provisional ballots Thursday. Those include ballots cast by voters who lacked photo identification. If the gap remains less than 1 percent, an automatic recount will be ordered Friday.

State Election Commission spokesman Chris Whitmire said the commission must meet again to certify those results, possibly Saturday. That would leave just 10 days to campaign before the runoff.

McKinney's campaign was already crafting its runoff schedule Wednesday.

"We're optimistic that we'll be in the runoff," said spokesman Taylor Hall. "We're excited to be able to bring our message to voters for the next two weeks."

Campbell said he's in a wait-and-see mode but will continue to communicate with supporters.

"We feel good about our position," said the 45-year-old small businessman. "This thing is far from over. We're right in the mix of it."

Earlier in the day, Campbell's campaign pointed to voting irregularities, saying Campbell's own precinct in northeast Richland County opened nearly an hour late. Whitmire said candidates have the ability to protest with their state party. But Campbell said he won't raise the issue.

"We're not engaging in any of that," he said.

Campbell spokesman Hogan Gidley called Campbell's showing strong, considering how little he spent in the campaign. Campbell, who entered the race in late March, was the only candidate among the top three who lacked a TV ad. His pre-election financial disclosure showed he received less than $39,000 total in contributions and had just $22,000 available as of May 30.

That compares to more than $586,000 McKinney received in contributions, plus an additional $245,000 he loaned himself, since announcing his candidacy last fall. The 64-year-old Charleston resident had $243,500 cash in his campaign account on May 26.

McMaster, 67, also got into the race in late March. The former two-term attorney general and U.S. attorney raised $225,400 between then and May 23, and had nearly $103,000 on hand.

"It's a testament to the grassroots, shoe-level campaign Mike ran that he was able to spend no money and be this close," Gidley said. "At the end of the day, I just don't think you can buy elections in this state."