That doesn’t wash in a right to work state. Besides, the energy sector counties didn’t vote for Heitkamp, it was mostly the East side of the state (the part without any oil). Reservations went Dem, as usual, but you could have run Abe Lincoln as a Democrat and they’d have voted for him—it’s a ticket vote (not sure why).
Hell, you could elect Custer's great-great-great grandson on the Rez, if you ran him as a Democrat.
That's who they get all the beads & trinkets from these days, in fact always have...and at present it is a LOT.