Cracking and packing are the two primary tools for drawing maps that minimize an opponent's representation. Cracking divides a concentrated community — a city, a minority neighborhood, a college town — across several districts where that community forms a small minority in each. Packing does the opposite: it stuffs as many of the opponent's voters as possible into a single district, where they win by huge margins that do not translate into additional seats.
Both techniques waste votes. A cracked community cannot reach a majority anywhere. A packed community wins one seat by 80 percent when a 55 percent win would suffice, spending the remaining margin on nothing. Skilled map-drawers use both in combination: crack the opponent's voters in most districts, pack the remainder into a sacrificial one. Tennessee's 2026 map cracked Memphis's Black community almost exactly into thirds across three districts — TN-2, TN-4, and TN-7 — where Black residents form a minority in each.
Identifying cracking or packing on a map is not always straightforward. When racial and partisan affiliation overlap heavily — as they do in Memphis — legislators can claim partisan intent while achieving racial effects, a defense that Rucho v. Common Cause (2019) strengthened by removing federal courts from partisan gerrymandering cases.
These techniques are how mapmakers convert geographic distributions of voters into structural advantages that last an entire decade. Understanding them is the minimum required to evaluate whether a proposed map is fair.
People often treat cracking and packing as purely racial tactics. They are used against any concentrated voting bloc — cities, universities, party-registration clusters — regardless of race. The racial dimension matters specifically when it triggers VRA or Equal Protection analysis.
These techniques are how mapmakers convert geographic distributions of voters into structural advantages that last an entire decade. Understanding them is the minimum required to evaluate whether a proposed map is fair.
People often treat cracking and packing as purely racial tactics. They are used against any concentrated voting bloc — cities, universities, party-registration clusters — regardless of race. The racial dimension matters specifically when it triggers VRA or Equal Protection analysis.