McCaskill passes on run for governor
© Greg Nash

Sen. Claire McCaskillClaire Conner McCaskillSenate Dems lock in million in TV airtime Why does Congress keep playing political games on FBI oversight? Red-state Dem tells Schumer to 'kiss my you know what' on Supreme Court vote MORE (D-Mo.) on Monday said she’d forgo a run at the governor’s mansion in her home state and would instead remain in the Senate.

“I’m convinced that where I can have the biggest impact is to remain in the United States Senate,” McCaskill told KCUR public radio in Kansas City, Mo., on Monday. 

“That’s a firm no,” she added in response to a question about whether she could potentially change her mind. 

McCaskill said her decision was made in part because she now has “significant seniority” in the upper chamber and is part of “much smaller group holding down the middle, the moderates that are able to talk to the extremes.”

“I look at the makeup of the current U.S. Senate and I see what might be possible in terms of me helping forge some of those compromises, and at the end of the day the work is too important, the job is too rewarding and too fulfilling,” she said.

“The trust that Missourians have put in me giving me this job, I don’t think I can move away from that, so I will not be running for governor in 2016.”

McCaskill isn’t up for reelection until 2018, but there was some speculation that she would return home before then to run for governor. McCaskill has run for governor in her home state before, losing narrowly in 2004 to Republican Matt Blunt, the son of Sen. Roy Blunt (R-Mo.).

Gov. Jay Nixon’s (D-Mo.) second term is up in 2016. His popularity in Missouri and his political fortunes nationwide have declined in recent months as he has been criticized for his handling of the protests over the shooting death of Mike Brown in Ferguson. 

McCaskill said her decision not to run for governor had nothing to do with polling or her popularity in Missouri. She said polls show she has the highest favorability rating among statewide elected officials over the last 60 days. 

“This isn’t about whether I would win or lose,” she said. “It’s about where I could make the biggest contribution, and I feel blessed to be at this point where I am at this moment in history.” 

McCaskill threw her weight behind state Attorney General Chris Koster (D) in the governor’s race. Had she decided to run for governor, it would have potentially set up a primary battle between herself and Koster, two political heavyweights in Missouri. 

“We have a terrific candidate that is ready to run for governor,” McCaskill said. “I look forward to working real hard for Chris Koster so that we will keep the sanity … amidst some pretty extreme folks who want to turn away from progress and turn away from the notion we can do better in Missouri.”

McCaskill won her Senate seat for the first time in 2006, edging out incumbent Sen. Jim Talent (R-Mo.). McCaskill coasted to a surprising reelection in 2012 by defeating gaffe-prone Rep. Todd Akin (R) in a landslide.

She was one of a handful of red-state Democratic senators considering a run for governor in their home states. Had she run for governor and won, she could have appointed her successor, making life easier for Democrats in a cycle when they hope to reclaim the Senate.

Still, the Democrats could have other holes to fill in red states.

Sen. Joe Manchin (D-W.Va.) has been vocal about his frustrations with gridlock on Capitol Hill and the leadership in his own party. Manchin has said he’s considering a return to his old job as governor of West Virginia, a post he held from 2005 to 2010.

Democrats would be hard-pressed to hold Manchin’s seat should he leave Washington. Republican Sen. Shelley Moore Capito crushed her Democratic opponent in 2014 by nearly 30 percentage points. 

And rumors are also swirling in North Dakota that Sen. Heidi Heitkamp (D) might run for governor in 2016.

The rumors have picked up enough steam that GOP lawmakers in the state have written legislation that would keep Heitkamp from appointing her successor.

If Heitkamp were to leave the Senate early, and if she were unable to appoint a successor, it would leave Democrats with another seat that would be difficult to hold in 2016. Heitkamp won her 2012 election by fewer than 3,000 votes, and Republicans have an ironclad majority at the state level in North Dakota.

This post was updated at 1 p.m.