A Diplomacy-like table top game (although possibly better as an educational computer game) where each player is given a certain amount of resources and then sent out from the East coast of the young America to settle the rest of the continent. Key points would be to create a territory with the existing geographical maps- with boundaries of your own design, and then get the requisite 60,000 people needed for official statehood to come there using legal or economic inducements. Natural boundaries such as rivers or mountains might make it easier for you to keep people in your area, but arbitrary borders look cleaner and might maximize your area.
Player interactions occur in a phase for bargaining, and perhaps battling, over the exact borders of a particular area- or possibly working together at times to create advertising back East for those with a pioneer spirit to head out West and try there luck. Extra resources would go to those with more states, so perhaps you could decide to try and create two or three states simultaneously out of space reserved for one, but would the smaller land area of each slow you down too much? Will the map end up looking anything like it does now? Will the 50 States become 100 States? Will Canada be happy where it is, or will some provinces start expanding south into weakly held areas?