Stitt, 46, a political newcomer who poured nearly $5 million of his own money into the race, managed to keep the state solidly in Republican hands and snuff out Democrats' best hopes for wresting control.
Stitt, who cast himself as an outsider in the mold of President Donald Trump, criticized his opponent, 72-year-old Drew Edmondson, as a career politician. Stitt also got a boost from a campaign stop last month with Vice President Mike Pence in Tulsa and an endorsement from Trump, who won the state with more than 65 percent of the vote in 2016.
"Oklahoma has all the resources we need to be a top 10 state, and I am ready to lead us there with your help," Stitt told supporters in Oklahoma City after he was declared the winner.
Attack ads against Stitt and Edmondson tried to link each of the candidates to term-limited Republican Gov. Mary Fallin, whose approval ratings have been dismal after years of state budget crises and a teacher walkout in the spring that shuttered schools for two weeks.
But many voters said they liked the fact that Stitt, the founder and former CEO of Gateway Mortgage Group, would bring a businessman's approach to the governor's office.
"I voted for Kevin Stitt for the sole purpose that he's a business owner, and we need someone who knows how to handle a business," said Alicia Lutz, 59, a retired housewife from the Oklahoma City enclave of Bethany. "The government is like a business, and that's why I voted for him."
Edmondson, who ran unsuccessfully for the Democratic nomination for governor in 2010, rarely mentioned Trump on the stump and focused instead on state issues like improving public schools and expanding Medicaid to cover more of the working poor.
He hoped teachers energized by the two-week walkout in the spring would give his campaign a boost and neutralize Stitt's advantage in rural parts of the state that have been trending Republican for decades.
"People are focused on the education of their children, which is where they ought to be focused," Edmondson said. "That's our future."
Libertarian Chris Powell also was on the ballot in the governor's race.
Stitt has said he would support raising teacher salaries even more, but he also has hammered an anti-tax message and said he would have opposed the tax hike the Republican-led Legislature approved this year to raise teacher salaries.
A relative unknown less than a year ago, Stitt defeated a 10-man GOP primary field that included Lt. Gov. Todd Lamb and former Oklahoma City Mayor Mick Cornett.
Republicans control all of state government in Oklahoma, but the conservative state has a propensity for electing a governor from the opposite party occupying the White House. But Edmondson, a Vietnam veteran and former state prosecutor, was unable to take advantage of that trend.
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