You would think that Biden would win Montana before Kansas but okay.
Not necessarily. I’m not sure KS has (had) similarly fast-growing conservative areas as MT, where Republican strength in counties like Flathead, Yellowstone, and to a lesser extent Ravalli has been fueled by oil workers, white evangelicals/social conservatives, small business owners, and retirees over the last two decades. That growth (by MT standards) has stalled somewhat, and new waves of migration (particularly into the Western part of the state) are definitely more D-friendly and should be a serious cause for concern if you’re the MTGOP and thinking long-term, but KS has so far experienced stronger Democratic trends in its most populous counties.
KS also has a larger non-white (especially African American) population and has seen less of an erosion of Democratic support in rural areas (in part because rural/small-town KS is essentially maxed out for the GOP) and among blue-collar workers/union voters than MT.
That’s not to say that MT wouldn’t be very close if Biden somehow won KS (it definitely would be), but it could certainly vote 1-3 points to the right of KS.
