What exactly is congressional redistricting?
The U.S. Constitution states that “representatives . . . shall be apportioned among the several states . . . according to their respective numbers.” It could well have added, “This activity shall be the meanest, nastiest, ugliest, and highest-stakes form of politics.” State legislatures must draw new congressional-district boundaries every ten years, based on the national census, so that the districts will be approximately equal in population. Redistricting is the process of redrawing these political maps.