"Following the American Declaration of Independence on July 4, 1776, the Thirteen Colonies engaged the British forces in the Revolutionary War. After the war ended, representatives from the colonies met to ratify the U.S. Constitution and select a leader. In Perfect Union, it is your task to influence the vote in each of the colonies so that your candidate gets elected president."
The game is played over seven rounds, with each player playing a single card from a fixed set each round. All the cards played in a round must be different. Most of the cards allow the player to place a certain number of pieces on the board, divided among the colonies as they wish. Two of the cards allow players to move already-placed pieces.
At the end of the game each colony is assessed and the player with the most pieces in each wins its votes. If there's a tie the colony is temporarily ignored. If no player reaches 22 votes the lowest player's pieces are removed from the board and everything is re-assessed.
The rules give no maximum number of players, but six seems reasonable.