As they sat down to draw the state’s congressional maps in 2021, Republican state lawmakers in charge of the once-a-decade process pored over detailed electoral and demographic data. This allowed them to pick with precision which voters they’d like to have in each district—a process known as gerrymandering. Typically, the party in control of the state legislature has two ways to protect its legislative and congressional candidates and weaken the power of voters who lean toward the opposition. “Packing” takes voters who favor the other party and places as many as possible in a single district, thus ceding one seat to political opponents but increasing the majority party’s odds in multiple adjacent districts. A second tactic, “cracking,” splits voters for the opposition into multiple districts that…