As required of all true wargames, I've been playing a rule wrong.
The Eastern Shore of Virginia is a separate territory, and that makes one great big difference in control of that colony, as you can only move to it from Maryland. Virginia is in the middle of everything, having contention in it means you can't reinforce Virginia locations on your turn. That one spit of land becomes quite strategic, and can be held by one lonely cube pretty effectively.
It's in my back yard, you think I would have figured that out on my own.