Considering the conservative nature of this state, the Republican primary is the only real contest in this gubernatorial election.
South Dakota has always been friendly to Democratic Senators and Congressmen, but not governors. I think the Democrats will go all in on the House race, but ignore the governor race.
Which is odd because its generally the opposite in most other places, but not the Dakotas.
I'm probably going off topic, but why is the House seat in Montana unwinnable for the Democrats? The Democrats don't seem to have much trouble with the Senate seats though.
Once an incumbent becomes entrenched it's hard to knock them off - Denny Rehberg became entrenched quickly, while Zinke got pretty lucky with two bad years for Democrats in a row, and at this point probably couldn't get knocked off even if the Dems tried in 2018. Luckily, Zinke is probably running for Senate, so Montana Dems might have a shot.