-Matt Blunt (R-MO) retired in 2008. I think he had some ethical scandals.
Email scandal involving his chief of staff and anti-abortion groups, plus polls were already showing him running behind Jay Nixon even 10 months out.
Missouri seems to like one-term governors. Bob Holden before Blunt was one-term as well, Greitens served less than half a term before resigning, and now Parson has said that if he wins this November he won't run again, so he would be "officially" one-term also.
I guess Nixon was the only governor this century who had both the desire and the scandal-free-ness necessary to get a second term.
