The Native American Vote

[minionofmidas]

A further note:

That's a pretty sizable rural population. It's also unusual for Whites on large, majority Native populated, reservations to be predominantly rural.
Unlike the Great Dakota reservations, Crow was allotted in severalty under the Dawes Act. But unlike at Flathead or Wind River, "surplus land" was not sold to Whites by the government. Instead, almost all the remaining land was allotted in severalty in 1920. A lot of it has passed back into tribal ownership since, some has passed into white fee-simple ownership, but a lot is simply leased to Whites (and often entangled in complex joint-inheritance disputes, as usual for Dawes Act land.)

In 1998, of the 2.282mio acres of the reservation,

456k were trust land in tribal ownership
1,014mio were individually owned trust land
46k were owned by the State of Montana
28k were owned by the tribe in fee simple (so the BIA has no say about that land)
37k were owned in fee simple by tribal members
701k had passed into White ownership.

The thing is, the Crow Reservation is located in the heart of the Mountain Crow's historical territory, where they have been living since the 1600s. The Bighorn Valley may have been remote in the frontier period, but it is fertile land. (Is anybody surprised why Sitting Bull's people chose to withdraw to here in the 1870s?)
 
In the late 1990s, there were 765 working farms on the reservation, of which only 74 were Indian-owned, and 176 working ranches, of which 60 were Indian-owned.
And that's your rural White population.

The absence of an urban White population is more quickly explained: Crow Agency is home only to the tribal administration and the Community College, not to state or county jobs - those are in Hardin. And Hardin is close enough to Crow Agency that Whites working in Crow Agency are probably more comfortable commuting in from Hardin, anyways.

[minionofmidas]

And there was a crazy suit by local whites in 2006 that wanted the Crows banned from manning their own polling stations because of some minor irregularities and because the Crow Nation had endorsed, and campaigned for, the (victorious) near all-Crow slate for county offices over an all-White one. Maybe that politicized some people?

Governor Schweitzer joked about tribal police chasing away Republican pollwatchers in 2006; the right-wing uproar over that remark couldn't have helped either.

One Republican pollwatcher. Yes, that incident was actually one of the two "minor irregularities" the suit was about.

[Alcon]

I thought that was Beltrami County, Minn.?

Edit: And, darn, no, I don't.  Could have sworn I entered Hardin.  I have: Blaine, Carter, Cascade, Custer, Dawson, Deer Lodge (hard one), Fallon (part), Garfield, Glacier (municipal), Hill (municipal + Rocky Boy areas), Jefferson, Judith Basin, Lake, Lewis and Clark (part), Liberty, Lincoln, Madison, Meagher (uni-precinct), Mineral, Missoula, Musselshell, Petroleum (uni-precinct), Phillips, Pondera, Prairie, Ravalli, Roosevelt, Sanders, Silver Bow (actually not all Butte), Stillwater, Teton, Treasure, Valley, Wheatland, Wibaux (uni-precinct) and Yellowstone.

[minionofmidas]

No Rosebud?

No matter, the election results and precinct sizes make it perfectly clear that Northern Cheyenne is precincts 15 and possibly 17. (there are only 12 precincts, but they bear strange numbers - 3, 6, 7, 10, 11, 15, 17, 20, 21, 26, 30, 32)
But I wonder whether that largest precinct, which very narrrowly went for McCain, is Colstrip (the largest town, and a huge coalmine) or the only slightly smaller county seat of Forsyth. The other one would have to be split between several precincts.