A former Republican state senator serving as treasurer of independent Greg Orman's campaign resigned Tuesday and endorsed Democratic nominee Laura Kelly, declaring her the only viable candidate for governor capable of uniting Kansans.

Tim Owens, a moderate Republican from Johnson County and an early advocate for Orman, said the time had come to step away from the Orman campaign and work to prevent election Nov. 6 of GOP nominee Kris Kobach.

“Electing Kris Kobach governor is one of the worst things that could happen to our state," said Owens, who served in the Senate under Gov. Sam Brownback. "For those of us who lived and worked in the Legislature through the dark Brownback years, we know just how damaging a return to those policies will be.

"And that is exactly what Kobach will do. The polarization he will bring to our state would be detrimental to the economic development of Kansas and damage our workforce."

Kelly said she appreciated the endorsement from Owens, and said "Republicans and Democrats know that I have the right priorities to move Kansas forward."

Orman, who fell short in an 2014 independent bid for U.S. Senate, said in a statement that he accepted Owens' resignation. Orman also criticized Kelly, a Topeka state senator, as an "establishment" candidate, but didn't mention Kobach, who serves as Kansas secretary of state.

"Tim believes that the best path forward is with an establishment candidate like Laura Kelly," Orman said. "I wish Tim well, but have told him that my campaign is about the people of Kansas, not about establishment figures in Topeka. As I've said since day one, I am committed to the tens-of-thousands of voters who support me and who are sick and tired of the status quo."

Recent polling indicated Kelly and Kobach were essentially tied, but Orman lagged behind in single digits, along with two other candidates.

“I’ve been a friend and colleague to Greg Orman for several years," Owens said. "I supported his run for Senate in 2014 and I until today supported his run for governor. However, this is a critical election for Kansas. We cannot risk the future of our state."

Owens was in the Senate from 2008 to 2013 and in the House from 2002 until 2008. From 1981 to 2005, he was on the Overland Park City Council.