What happens in Harrisburg doesn’t stay in Harrisburg: It’s about Washington, too.

The party that controls Pennsylvania’s legislature gets an outsize role in drawing maps of the state’s congressional districts, a decennial process known as redistricting that will happen again after the 2020 elections. That’s why national Democratic and Republican groups are setting their sights on Pennsylvania’s state capital as a way to help win power in the nation’s. They hope to win or hold seats in next year’s legislative elections. More than 200 seats in the state House and Senate are up for grabs, and winning just a few can determine control.

Democrats are already eyeing a potential takeover of the state House — flipping the Senate will be harder — and boatloads of money are set to pour into the state for the 2020 presidential race. But the attention of national redistricting groups could make next year’s down-ballot elections noisier and nastier than usual. And that, advocates fear, could distract voters and politicians from the need for nonpartisan redistricting reform.

“It’s going to be a very loud, very messy space," said Carol Kuniholm, head of Fair Districts PA, the grassroots organization that has helped make redistricting a bigger political issue in the state. "There’s going to be people trying hard to confuse things, there’s going to be people getting all sorts of strange messages, and it’s going to be lots of money. We need to reclaim a nonpartisan space for voters in Pennsylvania, we need to not get swept up in the horrible partisan divide and the toxic talking points.”

Once a decade after the census, states redraw their congressional and state legislative lines to ensure equal population across districts. Those maps can and often have been drawn to make it easier for one party or the other to win seats, a practice known as gerrymandering. Sweeping Republican victories in statehouses across the country in 2010 helped solidify GOP control of Congress for years. In Pennsylvania, the victories yielded a congressional map that was considered one of the most extreme partisan gerrymanders ever. The Pennsylvania Supreme Court last year threw out those maps and redrew new ones itself.

On one side as 2020 approaches, defending the current Republican majorities in both chambers, is the National Republican Redistricting Trust and the Republican State Leadership Committee. The RSLC ran a hugely successful operation to win statehouses and draw political maps in Republicans’ favor 10 years ago and hopes to repeat those wins with a new Right Lines 2020 project.

Opposing them and attempting to wrest control of Harrisburg from Republicans is the National Democratic Redistricting Committee, a group led by former Attorney General Eric Holder and backed by former President Barack Obama. The NDRC, which last year supported Pennsylvania Gov. Tom Wolf’s reelection in 2018 and Democratic wins in the legislature, is again focusing on the state House and Senate and has launched its All on the Line initiative.

The parties have a handful of states on their target lists, and Pennsylvania shows up on both. Democrats need a net gain of nine seats for a state House majority and four seats to capture the Senate.

“It’s no surprise that Pennsylvania is at the top of their lists, because the House in particular is one of the most flippable chambers in the country next year,” said State Rep. Leanne Krueger (D., Delaware), who chairs the House Democratic Campaign Committee, which seeks to elect Democrats to the state House. “National Republicans have been dumping money into Pennsylvania for decades. This time we are prepared to fight back.”

» READ MORE: Pennsylvania Democrats don’t just want to beat Trump in 2020: They want the state House back

Kuniholm said the partisan attention underscores that redistricting should be out of the hands of political parties altogether.

“Neither party wants fair [maps], both parties are coming at it from a partisan point of view,” she said. “Both sides play this game and right now we’re watching it play out again.”

But this may also be a unique moment, Kuniholm said, for Republicans to decide a fair map is better.

The state Supreme Court last year threw out the congressional maps Republicans drew in 2011, declaring them so gerrymandered that they violated the state constitution. Democrats will still have a majority on the court for any redistricting challenges that came out of the 2021 mapmaking, and Wolf’s reelection last year gives Democrats veto power over the congressional map drawn by the legislature. State House and Senate districts are drawn by a bipartisan commission with a tiebreaking chair appointed by the Supreme Court.

» READ MORE: Pennsylvania, gerrymandered: A guide to Pa.’s congressional map redistricting fight

So Republicans may find themselves hemmed in by a Democratic governor and the Supreme Court even if they control the legislature. Kuniholm voiced some hope that Republicans would consider reforming the process to produce politically neutral maps — even if only to prevent Democrats from giving in 2021 as good as they got in 2011.

“The stakes for redistricting are high,” NDRC spokesperson Patrick Rodenbush said. “The choice is between allowing Republican politicians to once again handpick their voters or finally having fair maps that let the people choose their representatives.”

A spokesperson for Wolf said the governor “believes strongly in independent redistricting” and “his focus will continue to be on ensuring Pennsylvania’s next set of maps meets a stronger standard for fairness.”

Republicans are skeptical, though, and have accused Democrats of seeking to gerrymander when they can. Democrats have been known to skew political maps, too, and 17 U.S. House seats is a juicy target. (Pennsylvania is expected to lose one of its 18 seats after next year’s census.)

“They’ve recruited liberal billionaires, labor unions, and left-wing activist groups to join them in a coordinated program to rig our nation’s legislative boundaries in favor of Democrats,” former U.S. House Speaker John Boehner said in an RSLC announcement about its efforts. “We have to stop them because the outcomes of these elections will have an ever-lasting impact on the future of our country.”

Charlie O’Neill, spokesperson for the Pennsylvania Republican Party, noted that “gerrymandering has entered the lexicon of the average voter.”

“It’s important and absolutely a part of our messaging that maintaining the control of the legislature is important for redistricting,” he said. “It’s important for a variety of things, but redistricting is definitely one of them.”