Going to North Dakota, it may be worth considering going around Chicago to the north. There are a few options, possibly depending on where in New York you're starting from. I-75 or whatever to the upper peninsula of Michigan and then US2 west is one. Cutting across Canada from Niagara Falls to Sarnia would make this somewhat more direct. Going all the way around the great lakes through Canada is also a decent possibility. Finally, there is a neat (but expensive) ferry between Ludington, MI and Manitowoc, WI: the SS Badger.
If it were me, I would probably go across Ontario and then take that ferry.