The congressional maps are all but set for the 2018 elections. But for those on the front lines of a simmering battle over the next decade of elections, the results are about more than who will control the next Congress.

This year’s election season could reveal just how much the current districts have entrenched an advantage for one political party over the other, whether courts will step in to stop state lawmakers from creating such partisan districts, and which party will control crucial local offices ahead of a nationwide redistricting based on the 2020 census.

The National Democratic Redistricting Committee — a new group led by former Attorney General Eric H. Holder Jr. that aims to spend $30 million this cycle — has targeted 20 legislative chambers, nine gubernatorial races and other races it considers the “most important for shifting the balance of power in the redistricting process.”

“This is a critical election year for redistricting because it is the first cycle where the officials elected will serve during the redistricting process in 2021,” the Democratic group said.

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The group spent money in two Minnesota special statehouse elections in February. And it supported a Democratic-preferred candidate in the Wisconsin Supreme Court election in April who it says will help defend the right to vote in that state.

The NDRC wants Democrats to wrest back control of the redistricting process from Republicans, who seized the advantage after the 2010 elections because they were in power when the census results came in and the redistricting process started.

In 2012, Republicans won a 33-seat majority in the House despite winning fewer than half of all votes. And the advantage stuck, the NDRC says.

Former Rep. Steve Israel said his experience as the two-time chairman of the Democratic Congressional Campaign Committee prompted him to travel around the country this year, talking to activists and donors about controlling the state political infrastructure.

“When I explain to them that we lost 1,000 Democratic local officials, including governors between 2008 and 2012, and they say, ‘How did that happen?’ I say, ‘Well, you guys let it happen. You guys let it happen. Don’t let it happen again,’” Israel said in March.

The Republican State Leadership Committee has plans of its own to defend the gains it made in controlling state legislatures after the 2010 census. Three years ago, the group launched REDMAP 2020, a reboot of an effort a decade ago, with a goal to raise $125 million to defend the legislative majorities that shaped the current congressional districts.

Court action

The Supreme Court could dramatically alter the landscape and how much those local officials can use politics to redraw the districts after 2020, with decisions expected before the end of June.

At one point, the focus for this election season’s redistricting efforts were high-profile legal challenges that called into question whether maps would have to be redrawn in Maryland, North Carolina and Texas.

But the Supreme Court has yet to rule in those cases, and legal experts say the justices are unlikely to require states to upend races that are already underway, even if they now find the maps unconstitutional.

All but 19 states will already have held primary contests before the high court’s term ends in June, and only Delaware and Louisiana have filing deadlines after that time.

The justices grappled with two cases about whether federal courts can hear challenges to a state’s political maps on the basis that they entrench a benefit to one political party over another. One case focuses on Wisconsin’s statehouse map, and the other deals with a Maryland congressional district, but both could have national implications depending on how the court rules.

An example of the impact of partisan gerrymandering can be seen in Pennsylvania, where the state’s Supreme Court in January required a new map for the 2018 election. The court struck down the Republican-drawn congressional map on a pioneering ruling that said it violated the state’s Constitution because it solidified an advantage for Republicans.

Though the Keystone State is competitive in presidential and gubernatorial elections, Republicans have won 13 of the state’s 18 House seats in the last three elections. The map shifted from 12 districts carried by Donald Trump and six by Hillary Clinton to 10 Trump districts and eight Clinton districts.

Entrenched to what extent?

Even that court-ordered redrawing of Pennsylvania’s congressional map won’t make much of a dent in the nationwide gerrymandering lead that Republicans built after the 2010 census, according to a study from the Brennan Center for Justice, a policy and legal institute that has been active in the latest partisan gerrymandering lawsuits.

The early indications about the 2018 midterms point to a wave election for Democrats, but the Brennan Center found that Democrats would have to win the national popular vote by nearly 11 percentage points to overcome maps designed to favor Republicans and gain control of the House.

One of the report’s authors, Michael Li, said he will be watching for how any Democratic wave election compares to past waves when it comes to how many seats are gained in Congress.

“I suspect at the end of the day they may have only a small majority, and that’s going to be a big lesson about the power of modern gerrymandering,” Li said.

And that ultimately could heighten scrutiny of redistricting in the 2020 elections.

“It’s certainly an issue that voters understand a lot more than they used to,” Li said. “It’s an issue that pops. Everybody, whether a Republican or Democrat, people understand it and they understand how it undermines democracy.”

Every state has its own way of redistricting, with the legislature in charge of the process in most. And some governors can veto the district lines. 

Of the states in which one party controls both the legislature and the governor’s office, Republicans are in charge in 20 and have an advantage in the redistricting process, compared to just two for Democrats, according to a review of data from the National Conference of State Legislatures, Ballotpedia and other sources.

In 14 states where there is divided control, it’s not as clear which party has a redistricting advantage.  

Six states have a bipartisan political or independent commission in charge of redistricting. Nebraska’s nonpartisan legislature controls that state’s process.

And seven states have only one congressional district and do not need congressional lines redrawn.

Some state maps have such an advantage for Republicans that a wave election won’t matter, the Brennan Center study found. In Michigan and Ohio, Democrats are not projected to win an additional seat under current maps even if Democrats match their exceptional performance in 2006 and 2008 — the best Democratic years in two decades in both those states.

In North Carolina, Democrats would win three of the state’s 13 congressional seats with 30 percent of the statewide vote share, but wouldn’t compete for a fourth seat until their share reached 53 percent, the study found.

The Brennan Center warns that gerrymandering after the 2020 census could be even more precise and create more enduring partisan advantages because of computer-assisted drawing of district boundaries. And that goes for both parties scrapping for an advantage, as well as the courts who could rein in extreme partisan gerrymandering.

“This decade, gerrymandering has helped Republicans. In the future, it may help Democrats,” the Brennan Center wrote. “Although this report focuses on Democrats, its warnings apply with equal force to Republicans.”