Polls have consistently shown Republican mortgage company owner Kevin Stitt, a 46-year-old political newcomer who casts himself in the mold of a businessman outsider like President Donald Trump, slightly ahead of Edmondson. But the race appears to be tightening. The Cook Political Report has moved it from "likely Republican" to "toss up," though FiveThirtyEight.com, which also analyzes political contests, still projects Stitt likely to win. A Libertarian, Chris Powell, also is running.
Despite Republicans' growing advantage in voter registration and recent dominance at the ballot box, there are signs the party's grip on power may be slipping after years of a sluggish state economy, budget crises and GOP tax cuts that forced deep cuts to state programs, especially public schools.
Over the last two years, Democrats have chipped away at the GOP's super majorities in the Legislature, winning a string of four special elections to claim seats previously held by Republicans, including two where the GOP incumbents stepped down amid sex scandals.
Democrats, particularly women , also appear to be energized by their opposition to Trump and by spring teacher walkouts in Republican-led states including Oklahoma, where schools shut down across the state while tens of thousands of educators and their supporters flooded the Capitol for two weeks of protests over school funding.
Sally's List, an Oklahoma group dedicated to recruiting and training politically liberal women for public office, endorsed about a dozen female candidates in each of the last two election cycles. This year, they've endorsed 45.
The group's executive director, Sara Jane Rose, said a growing interest among women seeking office "started with anti-Trump and gun violence, and then teachers sort of fell into that group, and also people looking at what's going on nationally with women mobilizing."
There are also signs of Democratic enthusiasm in rural areas where Republicans have made huge gains over the last two decades. In Pontotoc County, about 70 miles (110 kilometers) southeast of Oklahoma City, the local Democratic Party had to move its monthly meeting twice after attendance exploded following Trump's 2016 election. Two years ago, the party didn't field a single precinct officer. This year, it filled 24 of 27 positions, said local chairman Bobby Joe Trail.
Edmondson also is generating enthusiasm among teachers, whom he courted with frequent visits during the walkout. They made "Remember in November" their mantra after becoming frustrated with Fallin and the GOP-led Legislature.
During a recent campaign stop at JD's diner in the Pontotoc County community of Ada, Edmondson hit on familiar themes that he hopes will help neutralize Stitt's advantage in rural areas: improving public schools and expanding Medicaid to cover more of the working poor.
Those sounded like good ideas to 72-year-old local Ronald Boggs. "The top two issues to me are education and health care," Boggs said. "I think education hasn't been sufficiently funded and we don't pay our teachers enough."
Pat McFerron, a Republican political strategist and pollster, said that while he expects Stitt to win, Edmondson has been able to take advantage of growing discontent among voters with the direction the state is moving, particularly when it comes to education.
"I jokingly say the top three issues in the state are education, education funding and teacher pay," McFerron said. "And on education issues, right or wrong, Democrats have an advantage." McFerron said Stitt's opposition to this year's tax hikes that funded the teacher pay raise also "is damaging when that's the top issue voters are talking about."
Stitt says despite his opposition to taxes, he supports raising teacher pay even more. And while he recognized the race is tight, he said his lack of political experience is a benefit. "I think we have to have an outsider, a business person," Stitt told a packed crowd at a coffeehouse in the Oklahoma City enclave of Bethany.
Stitt also has amassed more than twice as much money as Edmondson, raising $10 million for his campaign, including nearly $5 million of his own money. Oklahoma Republican Party Chair Pam Pollard agreed there is a rising level of enthusiasm among Oklahoma voters but that it also extends to Republicans, particularly after the testy Senate confirmation hearings for Supreme Court Justice Brett Kavanaugh .
"I don't see and hear the blue wave. I don't," Pollard said. "There's a lot of talk out there, but when I take a look at the polls, we're in good shape."
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For the AP's complete coverage of the U.S. midterm elections: http://apne.ws/APPolitics