Henry McMaster and John Warren (copy)

Gov. Henry McMaster (left) and John Warren. File/Grace Alford/Staff 

COLUMBIA — The math seems to work in Gov. Henry McMaster's favor in his upcoming Republican governor's runoff against political newcomer John Warren.

But voter interest for another fierce race in his backyard, as well as possible help from former rivals, could improve Warren's chances for an upset on June 26.

"This is not over for McMaster," Greenville political consultant Chip Felkel said. "But Warren has a lot of work cut out for him."

Warren, who along with three other challengers, managed to keep McMaster from winning outright during Tuesday's primary, despite the governor having the coveted endorsement from President Donald Trump.

McMaster, promoted to governor last year after Nikki Haley left for the United Nations, was the top vote-getter with 42 percent. Warren, who runs a Greenville specialty real estate lender, nabbed 28 percent.

The governor's performance in the GOP voter-rich Upstate gave him the edge Tuesday.

When McMaster finished third in the 2010 Republican governor's primary, just one of out eight Upstate voters cast a ballot for him. On Tuesday, he got one of every three votes in the Greenville-centered region.

Warren did receive nearly 2,000 more votes than McMaster in the Upstate. But the governor collected 53,000 more votes statewide because he was less reliant on support from the state's northwest corridor. 

Nearly half of Warren's total votes Tuesday came from the Upstate. For McMaster, it was just 31 percent. The governor doubled the Marine combat veteran's vote tally in the Midlands and along the coast.

Still, two major candidates who lost Tuesday, Mount Pleasant attorney Catherine Templeton and Lt. Gov. Kevin Bryant of Anderson, could help Warren with endorsements. Between them, they received 28 percent of the vote.

Neither could be reached for comment Wednesday, but it would not be a surprise if they backed Warren since they all shared ideals that they were better suited to reform state government than McMaster, a career politician who was appearing on a statewide ballot for the fifth time in 16 years.

Voters will get more time to learn about Warren, who joined the race late just before Valentine's Day.

"People who hesitated to support John said they are not sure it was a viable candidacy," said state Rep. Micah Caskey, who backed Templeton. "But when they opened the papers today, they saw he was a formidable character."

Warren also could benefit from an expected fierce GOP runoff in Greenville and Spartanburg counties for the 4th Congressional District seat. More voters might be willing to hit the polls to choose U.S. Rep. Trey Gowdy's likely successor as well as pick a nominee for governor, Felkel said.

Still, McMaster always has a big hammer to swing — Trump. His campaign launched an ad featuring his ties to the president on Wednesday, a common theme in TV spots before Tuesday's primary.

As McMaster attacks Warren for being a "rookie," Warren could learn from the failed bid of another political outsider: Templeton.

An early favorite to beat McMaster, she failed to reach the runoff after her campaign and a pro-Templeton group combined spent more than $6 million. By comparison, McMaster and a pro-McMaster group spent about $5 million, while Warren kicked in $3 million of his own money. 

Templeton, a former two-time state agency chief, ran a frantic campaign as a self-proclaimed "buzzsaw" where she latched onto fringe issues like the Confederacy and lashed out at McMaster for being tied to subjects like the Statehouse corruption probe and at Warren for not being conservative enough.

The attacks didn't work, and she finished third with 21 percent of the vote.

"Catherine could not get away from making the campaign intensely personal instead of policy-based," said Rob Godfrey, a former top aide to Haley who worked for McMaster's 2010 campaign. "She really had this ax to grind."

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Columbia Bureau Chief

Shain runs The Post and Courier's team based in South Carolina's capital city. He was editor of Free Times and has been a reporter and editor for newspapers in Charlotte, Columbia and Myrtle Beach.