How about being able to mark off an area in the editor for a color? So it'd be a lower color (like red and dark red).
Say you have 20 states and you have that section green, then why not have a bigger box that you could make behind those 20 states with a dark green color. The states stay green, but the panel behind them is dark green? Then the section has 15 states in red, then made a dark red box/panel behind them.
This way you could mark off areas behind the states as 'panels' when your sections are. Also allow a 'header' so you could label each section.