"North Carolina and Texas have a history of some of the worst gerrymandering in the country," said Kelly Ward Burton, the president of the National Democratic Redistricting Committee, an initiative formed to break the GOP's hold on the map-drawing process. "And so the ability to move from extreme gerrymandering into fair maps is incredibly notable."

Thanks to curbs on gerrymandering forced by voter initiatives and public pressure, along with the 2018 midterm elections, Democrats have already made up some of the ground they lost to Republicans after 2010. That year's wave election helped keep the GOP in the House majority for eight years and in control of many state legislative chambers for the entire decade.

After flipping several governors’ mansions, Democrats have already improved their position from 2010. And they have other promising 2020 targets that will impact redistricting: Democrats are just two seats away from capturing the Minnesota state Senate and securing complete control of state government. And the party also has a path to power in both chambers of the legislature in Pennsylvania, where they already have a Democratic governor with veto power and a state Supreme Court that in 2018 tossed out a GOP-drawn congressional map as unfairly partisan.

But North Carolina and Texas are so important because they are large, growing states entirely under GOP control — and many of the other maps Republicans drew a decade ago have stubbornly endured, blunting Democratic gains. Privately, many Democrats concede they have no chance to flip any chamber in Ohio or Wisconsin, and only a narrow path to gaining control of the Florida state House.

Democratic strategists in Texas say 15 to 20 GOP-held seats will host competitive races, most of which lie in the quickly diversifying suburbs. Several of those are open seats, thanks to Republican retirements, and nine of them were carried by then-Rep. Beto O'Rourke in his 2018 Senate bid. Texas Democrats have mimicked the national party’s successful 2018 strategy, recruiting several women of color and veterans who are capitalizing on suburban disgust of President Donald Trump.

"In all these districts, in the polls I’ve seen, the president is definitely upside down in terms of his favorable rating. And that is hurting the entire Republican ticket," said Texas state House Democratic Caucus chair Chris Turner. "This is definitely the biggest battlefield for the state House that I can remember at least since my election, which was in 2008."

A number of groups are spending to boost Democrats in Texas, including the NDRC and Democrats' national legislative campaign arm. Forward Majority, a new Democratic group dedicated to winning state races, recently announced plans to spend $6.2 million across 18 races. Mike Bloomberg's Everytown for Gun Safety group has committed at least $2.5 million.

But many Democrats still expect to outspent in most races by well-financed GOP incumbents and their allies. Former Bush adviser Karl Rove is helping with a new Texas-centered PAC that plans to raise millions. And the Republican State Leadership Committee, the GOP's legislative campaign arm, has said it will invest more in Texas than in any other state and that it would outspend Forward Majority.

"There's an effort that we haven't seen in decades in Texas," RSLC President Austin Chambers said in a briefing last week. "That's come together. Republicans are going to outspend Democrats. And we've got a hell of an operation that's together down there."

Chambers said his group’s second-biggest priority is North Carolina, where the GOP has just a six-seat majority in the state House and a five-seat advantage in the state Senate. Democratic Gov. Roy Cooper is favored to win reelection, but he has no veto power over the map under state law.

North Carolina Democrats openly fret they are hindered by maps drawn to give Republicans an advantage. And even after a court-mandated redistricting in 2019 made those maps more favorable to Democrats, operatives still warn that they are competing on unfriendly turf. They are targeting roughly a dozen seats in the lower chamber and nine in the upper, including many clustered around Charlotte and the Research Triangle.

Yet financing has been a bright spot; a rash of Democratic state House and Senate candidates dwarfed the fundraising of their GOP challengers in the second quarter — a disparity that shocked Republicans and motivated them to redouble their efforts.

“The numbers from the last quarter were a complete wake-up call for our party,” said Pat Sebastian, a GOP operative in the state. “I mean, the Democrats really kicked our butt with fundraising, and you’re seeing a lot of our donors catch up. They got the picture now.”

Democratic operatives see the greatest opportunity in areas where rapid demographic change is diluting the GOP’s edge. Forward Majority is funneling its resources toward four growing states: Texas, North Carolina, Florida and Arizona — largely abandoning the Rust Belt targets it went after in 2018.

“Democratic performance in state legislative races underperformed the congressional wave of 2018, and a lot of pundits said, ‘Well that’s gerrymandering,’” said Vicky Hausman, a co-founder of the group. That’s true, she agreed, in Michigan, Wisconsin and Pennsylvania, where the population is static.

“It’s not true in the Sun Belt, where we’ve just seen so much population growth and diversification in the suburbs essentially blur the lines of the gerrymanders,” she said. “They just don’t hold.”

Democrats face long odds in Florida, where they need 14 seats to reclaim the state House, but some strategists think Biden's coattails could bring it within reach. And the party is seriously targeting both chambers of the Arizona legislature, where they need only a few seats for a majority.

But in Arizona, an independent commission redraws the congressional map — making it a less appealing target for groups trying to influence the balance of power on Capitol Hill. The same is true in Iowa and Michigan — where Democrats are only four seats away from capturing the lower chamber in each state.

Democrats will rely heavily on their success electing governors in Pennsylvania, Wisconsin and Kansas to gain a toehold on the redistricting process in those states, though there are limits to their power.

If a governor and legislature cannot agree on a redistricting plan, the map often ends up in court, and the mapmaking power is often wielded by sometimes-partisan judges or relegated to a court-appointed special master — unless the GOP has a supermajority to override a veto.

National Democrats are spending to break supermajorities in Kansas and to block Republicans from reclaiming a supermajority in Wisconsin.

In Ohio, a new redistricting law requires 50 percent of all members of the minority party in the legislature to approve a new map. The NDRC has spent $175,000 in Ohio this cycle, targeting the state house in the hopes of increasing the threshold of Democrats who will need to OK the legislature’s proposed map.

The fact that such redistricting reform ballot initiatives and commissions have proved popular with voters is another encouraging sign to Democrats, who have also been angling for a culture shift, hoping to increase the political pressure on lawmakers to draw reasonable maps.

“There’s just much more accountability on this process from the outside,” said Jessica Post, the president of the Democratic Legislative Campaign Committee. “It will be much more difficult for Republicans to go back into their bunkers and use state resources to hire private law firms and block access to private records because the public is watching much more closely than they were in 2012.”