BC and WA is an obvious one, though there are definitely crucial differences, our cultures and geography are similar enough where I think the comparison is apt.
Ditto with the Maritimes and New England.
Quebec is pretty unique, for obvious reasons.
The Alberta-Texas comparison is a frequently made one, though honestly I think Alberta is more like Idaho/Montana/Wyoming.
I agree with the Ontario/Ohio comparison. Ontario is pretty similar culturally and demographically to the lower American Midwest, including much of Ohio.
For the Maritimes/New England comparison, New Brunswick and Maine are especially similar.
