This article is from the archive of our partner National Journal

As Democrats seek to cut into Republicans' firm control of the House of Representatives, a handful of lawsuits over alleged gerrymandering give them hope that congressional lines in several states may become more favorable for them. But another suit before the Supreme Court could swing more districts against Democrats.

Both parties are awaiting court rulings in Florida, North Carolina, Texas, and Virginia—states where Republicans control the legislature and majorities of each congressional delegation. If the courts side with the plaintiffs, Democrats hope that two districts in Virginia and one in Florida will turn from safe Republican to competitive districts. In Texas, they hope a swing district held by a Republican will become more Democratic-leaning territory. And in North Carolina, the extent of the alleged Republican gerrymandering is so great that Democrats say they don't know where they stand to benefit the most.

Those scenarios depend on whether state and federal district courts side with Democrats. At issue is the Voting Rights Act, which requires that congressional districts group enough minority voters together so they can elect a candidate of their choice. That could mean Hispanics and African Americans must make up a majority of voters in a single district. But in some cases, a simple majority could be too little or too much.

In Texas, plaintiffs have argued that Republican mapmakers intentionally drew one district to look "majority-minority" in terms of raw population but not in actual elections. In several states, though, plaintiffs have complained of too many minority Democratic voters packed into single districts, diluting their influence on local politics. In Virginia, North Carolina, and Florida, oddly shaped districts snake across the state, connecting one urban metro area to another, consolidating minorities into a lower number of districts and allowing Republicans to control a disproportionately high number of districts.

Loyola (California) Law School professor Justin Levitt, who focuses on election laws and filed an amicus brief criticizing North Carolina's congressional lines, wrote that Republicans in some of these states followed a "simplistic demographic cartoon of the Voting Rights Act," drawing lines based on race without regard to other political factors.

But attorney Mike Carvin, who defended Virginia's Republican-drawn maps, said its lawsuit—and others—need to prove that race was the primary factor in the gerrymandering, not other factors such as incumbency protection. In Virginia, he said, the maps were drawn primary to protect incumbents of both parties, not to limit minorities' influence.

In all the gerrymandering lawsuits, Democrats are accusing Republican-controlled legislatures of gaining an advantage by packing Hispanic and African-American Democrats into a few districts. And the GOP does have a major advantage in all these states: They control 10 of 13 House seats in North Carolina, 8 of 11 in Virginia, and 25 of 36 in Texas.

Republicans do, however, stand to gain from a lawsuit unrelated to gerrymandering, challenging the constitutionality of independent redistricting commissions. If the Supreme Court sides with the GOP-controlled Arizona legislature this summer, Republicans are expected to turn at least one swing district, and maybe two, into a Republican-leaning territory.

Below are some of the incumbents most endangered by possible court rulings that could make their districts tougher to defend.

Virginia: Republican Reps. Randy Forbes and Scott Rigell

Forbes's and Rigell's Virginia districts are adjacent to Democratic Rep. Bobby Scott's deep blue, 56 percent African American district, which stretches from the urban center of Richmond to Norfolk, taking in part of Hampton along the way.

If a court orders legislators to redraw the lines and they choose to exclude Norfolk—which is only connected to the rest of Scott's district by a portion of the James River—either Forbes or Rigell would absorb a Democratic-leaning population center. Rigell's district supported President Obama in 2012 by a 2-point margin, and Forbes's went for Mitt Romney by just 1 percentage point.

Scott said it's unclear whether the courts take incumbency into account, but that he could lose a significant number of African American Democratic voters and still have a safe path to reelection.

Texas: Republican Rep. Will Hurd

Unlike the other Republicans whose districts are targeted by these lawsuits, Hurd is a Republican representing a majority-Hispanic district that Democrats say should have an even stronger Hispanic presence. Plaintiffs have argued that GOP legislators drew this district map to include a majority Hispanic population—while taking care to include Hispanics from areas with the lowest voter turnout to make up the numbers. That makes the district somewhat of an anomaly: It is 70 percent Hispanic, but it backed Mitt Romney in 2012.

"Texas claimed that the only necessary measurement of an effect on minority voters' ability to elect candidates of choice is a basic headcount," Levitt wrote.

Turnout plummeted in 2014, when Hurd unseated then-Rep. Pete Gallego, a Democrat. But if the district is redrawn, Democrats hope it will include an even bigger Hispanic majority, one that has higher voter turnout.

Florida: Republican Rep. Daniel Webster

Webster's district lies at the south end of Democratic Rep. Corrine Brown's district, which stretches about 150 miles from Jacksonville to Orlando, taking in densely populated areas in both metro areas, as well as in Gainesville.

The state Supreme Court ruled that state legislators crafted Brown's district based on racial statistics, without regard to voter registration and political affiliation, encompassing more areas dominated by minorities than necessary to elect an African American.

Pending an appeal, Webster's district may go from an entirely suburban and rural area in central Florida to one that encompasses a more urban portion of Orlando. His district is 76 percent white, but it only supported Romney by an 8-point margin in 2012 (when Webster faced a tough reelection race), meaning that a large group of Democratic voters could move him into a swing seat.

North Carolina: Various Republicans

Democratic Rep. G.K. Butterfield said Republican legislators "surgically removed white communities from my district and included more African American voters." And plaintiffs have argued the same thing happened to the state's two other Democratic districts, held by Reps. Alma Adams and David Price. 

All three Democratic districts are oddly shaped, winding throughout the state to include heavily minority, Democratic areas. Butterfield's is centered in the northern portion of the state but branches off to the west to include Durham and to the east to include Elizabeth City. Adams's stretches from Greensboro to Charlotte, with a western branch snaking over to Winston-Salem. And Price's includes parts of Raleigh, Chapel Hill, Burlington, and Fayetteville.

Most of the 10 Republican-held districts border one of those three Democratic districts, which means Democrats don't know exactly how they would benefit if the court rules in favor of the plaintiffs.

"I don't know which districts will be most affected because there are many scenarios that could be used," Butterfield said.

Republican state Sen. Bob Rucho, though, is confident that this case is less likely to lead to a redraw than the others, because it relates to a different section of the Voting Rights Act. Under that section, certain districts—including the ones in question in North Carolina, Rucho said—are required to consist of at least 50 percent racial minorities. Unlike legislators in Virginia, he was following a rule that essentially required a greater level of racial gerrymandering.

Arizona: Democratic Reps. Ann Kirkpatrick and Kyrsten Sinema

Separate from the gerrymandering debates, another lawsuit could shake the congressional landscape in the other direction, possibly giving Arizona Republicans an advantage. The Supreme Court will decide by the end of its term in June whether independent redistricting commissions, like the one that drew Arizona's districts, have the constitutional authority to draw congressional and state legislative lines. If it sides against Arizona's commission, the state's Republican-led legislature will likely redraw the state's districts for 2016.

Former state House Speaker Andy Tobin, who is considering running for Congress again after a failed bid in 2014, told National Journal in February that the legislature likely would shift Republican voters out of GOP Rep. Paul Gosar's deep-red district into one of the state's three swing seats. That would either hurt Kirkpatrick's or Sinema's chances at reelection, or shore up Republican Rep. Martha McSally's shot at winning a second term.

This article is from the archive of our partner National Journal.

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