Democratic gerrymandering is the practice of drawing electoral district lines to favor Democratic candidates, and it happens in the minority of states where Democrats fully control the map-drawing process — most visibly Illinois, Maryland, New York, and New Mexico after the 2020 census, and now California under a mid-decade redraw voters approved in November 2025. Republicans control more of the redistricting process nationally, but Democrats have pursued aggressive maps where they can and, since mid-2025, have joined an escalating retaliatory redistricting war.
How Partisan Map-Drawing Works
Two techniques do most of the work. “Cracking” splits voters of the opposing party across multiple districts so they cannot form a majority in any one of them. “Packing” concentrates opposing voters into a small number of districts, letting them win those seats by huge margins while wasting their votes everywhere else. Both parties use these tools, and the result is a gap between a party’s statewide vote share and the seats it wins.1Brennan Center for Justice. Gerrymandering Explained
Where Democrats Draw the Maps
Following the 2020 census, seven states drew congressional maps under full Democratic legislative control, covering roughly 11 percent of U.S. House seats. Republicans controlled the process in 19 states covering 41 percent of seats.2Brennan Center for Justice. Who Controlled Redistricting in Every State Within that smaller footprint, several Democratic-drawn maps stand out.
Illinois
Illinois Democrats, led in the state House by Rep. Lisa Hernandez, drew 2021 congressional maps that dismantled two Republican-leaning seats, including that of Rep. Adam Kinzinger, and reduced Republican representation to 3 of the state’s 17 districts.2Brennan Center for Justice. Who Controlled Redistricting in Every State The Princeton Gerrymandering Project gave the resulting Illinois House map an “F” for compactness.3Capitol News Illinois. Supreme Court Rules House Republicans Waited Too Long to Challenge Maps Three federal lawsuits challenged the maps as racial gerrymanders or Voting Rights Act violations. A three-judge panel rejected all of them in December 2021, finding that partisanship rather than race was the predominant factor.4Brennan Center for Justice. Redistricting Litigation Roundup A later state-level challenge from House Republican Leader Tony McCombie was dismissed by the Illinois Supreme Court in April 2025 as untimely.
Maryland
Maryland has been the clearest long-running example. After the 2010 census, Democratic leaders redrew the Sixth Congressional District by adding heavily Democratic areas near Washington, D.C., flipping a seat Republicans had held for nearly 20 years and locking in seven of eight congressional seats for Democrats.5Brennan Center for Justice. 5 Things to Know About the Maryland Partisan Gerrymandering Case Republican voters challenged the map in Benisek v. Lamone, and a trial court ruled in 2018 that the Sixth District violated the First Amendment.6Common Cause. Lamone v. Benisek Amicus Brief The Supreme Court took the case but decided it alongside Rucho v. Common Cause in 2019, closing federal courts to partisan gerrymandering claims entirely.
After the 2020 census, Democrats again drew an aggressive congressional map. Republican Governor Larry Hogan vetoed it; the Democratic-led General Assembly overrode the veto. In March 2022, Senior Judge Lynne Battaglia struck down the map as “an outlier and a product of extreme partisan gerrymandering,” finding Republican voters had been removed from the First Congressional District with “near surgical precision.”7Maryland Matters. Judge Throws Out Congressional Map, Orders Legislature to Try Again Democrats drew the replacement.
New York
New York’s process collapsed twice. A 2014 constitutional amendment created a bipartisan advisory commission, but the commission deadlocked in 2021 after Democrats won a supermajority in both chambers. Democrats then passed their own maps, which the state’s highest court struck down in April 2022 as a “highly aggressive gerrymander.”2Brennan Center for Justice. Who Controlled Redistricting in Every State A court-appointed special master drew replacement districts widely regarded as among the most competitive in the country.8Brennan Center for Justice. What Went Wrong With New York’s Redistricting
In 2024, the legislature rejected an Independent Redistricting Commission proposal and passed its own map. That map is now in litigation. In January 2026, a state trial court struck down the Eleventh Congressional District as racially dilutive under the state constitution.9NPR. Supreme Court Blocks New York Redistricting The U.S. Supreme Court stayed that ruling on March 2, 2026, in a 6-3 decision, with Justice Alito calling the trial court’s order “unadorned racial discrimination” and the three liberal justices dissenting.10SCOTUSblog. Supreme Court Grants Republicans’ Request to Pause Order to Redraw New York Congressional Map The stay remains in effect while the case moves through New York’s appellate courts.
New Mexico
New Mexico’s 2021 redistricting was the first to use a new advisory body, the Citizen Redistricting Committee, with final authority still resting with the legislature. Democrats enacted a congressional map in January 2022 that created a majority people-of-color district in southeastern New Mexico. Republicans challenged the map, and in July 2023 the New Mexico Supreme Court ruled that “extreme partisan gerrymandering violates the New Mexico Constitution,” ordering further proceedings in a trial court.11Common Cause. New Mexico Redistricting Resources
The 2025–2026 Retaliatory Redistricting Fight
The balance shifted in mid-2025, when a wave of mid-decade redraws broke the norm that redistricting happens only after a census. Texas triggered it. Governor Greg Abbott called a special session at President Donald Trump’s urging to redraw congressional districts with the explicit goal of converting five Democratic seats into Republican ones.12Harvard Kennedy School. Understanding the Mid-Decade Redistricting Push in Texas Texas enacted the maps on August 29, 2025.13NCSL. Changing the Maps: Tracking Mid-Decade Redistricting Voluntary mid-cycle redistricting for partisan advantage is extremely rare; since 1970, only Texas in 2003 and Georgia in 2005 had previously done it.14Pew Research Center. Redistricting Between Censuses
California answered on the same day. On August 21, 2025, Governor Gavin Newsom signed the “Election Rigging Response Act,” and the legislature voted on party lines to suspend the state’s independent redistricting commission and replace its congressional map with one designed to flip five Republican-held seats and strengthen Democratic margins in three more.15CalMatters. California Redistricting Vote The measure went to voters as Proposition 50 in a November 4, 2025 special election. Newsom framed it as temporary, with a provision returning California to nonpartisan map-drawing after the 2030 census.16The Conversation. Tit-for-Tat Gerrymandering Wars Won’t End Soon The Prop 50 maps were structurally similar to the existing commission-drawn map in racial representation and geographic compactness, though slightly less compact by standard measurements.17PPIC. How Would the Prop 50 Redistricting Plan Affect Racial and Geographic Representation
The pattern spread. As of mid-2026, more than 25 percent of all congressional seats have been redrawn mid-decade.18Harvard Kennedy School. What’s Happening With Gerrymandering in the United States On the Democratic side of that ledger:
- Virginia’s Democratic-controlled legislature passed a constitutional amendment authorizing mid-decade redistricting, and voters approved it in an April 21, 2026 referendum. The Supreme Court of Virginia invalidated the amendment on May 8, 2026, ruling that the General Assembly had violated procedural requirements in the state constitution. The 2021 maps remain in effect for the 2026 elections.19Virginia Public Access Project. Redistricting 2026
- Maryland’s state House passed a proposal in February 2026 for new maps together with a constitutional amendment to be placed on the November 2026 ballot.13NCSL. Changing the Maps: Tracking Mid-Decade Redistricting
- Washington legislators prefiled a proposed constitutional amendment in January 2026 that would authorize the state legislature to draw new congressional maps whenever another state undertakes mid-decade redistricting absent a court order.13NCSL. Changing the Maps: Tracking Mid-Decade Redistricting
Florida, on the Republican side, passed a new map aimed at eliminating four Democratic-held seats.18Harvard Kennedy School. What’s Happening With Gerrymandering in the United States
How Much Does It Actually Move the House?
A study published in the Proceedings of the National Academy of Sciences in June 2023 by researchers at Yale, Harvard, and MIT found that partisan gerrymandering is widespread in both directions but that its effects “mostly cancel” nationally. The net product of the 2020-cycle maps was roughly a two-seat advantage for Republicans in the U.S. House. Democrats face a larger structural disadvantage of about eight seats, but the study attributed most of that gap to geography, particularly the concentration of Democratic voters in urban areas, not to gerrymandering.20PNAS. Widespread Partisan Gerrymandering Mostly Cancels Nationally, but Reduces Electoral Competition
Under the enacted 2022 maps, the study estimated Democrats needed more than 51.1 percent of the national two-party popular vote to win a House majority, only 0.14 percentage points higher than under simulated nonpartisan maps. The larger effect of gerrymandering by both parties was on competition: 34 highly competitive districts nationwide under the real plans, compared to 50 under a nonpartisan baseline. The House was also less responsive to voter swings, with a one-percentage-point shift yielding about 7.8 seats under the real maps versus 9.2 under nonpartisan ones.21Yale ISPS. Partisan Gerrymandering Mostly Cancels Out at National Level, Study Shows The Brennan Center for Justice was more critical, estimating that the maps used in the 2024 election produced 16 fewer Democratic or Democratic-leaning seats than maps meeting the standards of the proposed federal Freedom to Vote Act.1Brennan Center for Justice. Gerrymandering Explained
Why the Courts Aren’t Stopping This
Two Supreme Court decisions define what challengers can and cannot do.
Rucho v. Common Cause (2019)
In a 5-4 decision written by Chief Justice John Roberts, the Court held that partisan gerrymandering claims are “political questions beyond the reach of the federal courts.” The majority found no “limited and precise” constitutional standard for deciding when partisan considerations have “gone too far.” Justice Elena Kagan dissented, writing that the ruling allowed “extreme” gerrymandering to persist and “debased and dishonored our democracy.”22SCOTUSblog. No Role for Courts in Partisan Gerrymandering The ruling ended the Maryland challenge in Benisek v. Lamone along with pending cases elsewhere, and shifted the fight to state courts and legislatures.23U.S. Supreme Court. Rucho v. Common Cause, 588 U.S. (2019)
Louisiana v. Callais (2026)
On April 29, 2026, the Court ruled 6-3, in an opinion by Justice Alito, that Section 2 of the Voting Rights Act can impose liability only where the evidence supports “a strong inference that intentional discrimination occurred.”24U.S. Supreme Court. Louisiana v. Callais By requiring proof of intentional racial discrimination rather than discriminatory effect, the decision substantially raised the bar for challenging maps on racial grounds. Civil rights organizations described the ruling as effectively neutralizing Section 2 as a tool for protecting minority voting power.18Harvard Kennedy School. What’s Happening With Gerrymandering in the United States In the immediate aftermath, calls emerged in several Southern states to redraw maps to eliminate majority-minority districts. Tennessee’s legislature had already divided Memphis, previously a single compact congressional district, into three districts stretching roughly 200 miles each.25Mississippi Today. Callais Redistricting Supreme Court
The Democratic Redistricting Operation
Democrats coordinate their redistricting strategy through the National Democratic Redistricting Committee, founded in 2017 by former Attorney General Eric Holder with support from President Barack Obama and Speaker Emerita Nancy Pelosi. The group treats redistricting as a decade-long effort rather than a once-a-census event, with stated goals of fighting maps it considers unfair, breaking Republican control of the process, and building grassroots power for future cycles.26NDRC. Our Strategy The NDRC’s affiliated PAC reported nearly $2 million in receipts during the first quarter of the 2025–2026 cycle, funded almost entirely by individual contributions.27FEC. National Democratic Redistricting PAC The organization has endorsed candidates for state offices central to redistricting, including races for governor, secretary of state, and state legislature seats in Pennsylvania and Ohio ahead of 2026 elections.