It may not be too late to prevent the partisan gerrymandering of electoral maps that Republicans believe will deliver them control of the US House of Representatives in 2022—as well as a tighter grip on the statehouses that will set so many of the rules for the 2024 presidential election. But it is almost too late.

Ten years ago, Republican governors and legislators used the redistricting process that extended from the 2010 Census to gain dramatic political advantages. Now, with the release of fresh Census data, they are poised to do so again. No one should doubt what is at stake. If the supporters of voter suppression succeed, they could deny Americans representation based on the racial and ethnic diversity that the new data reveals.

“States have long been preparing for this moment, and they now have the green light to start gerrymandering. If left unchecked, this year’s redistricting cycle represents a severe threat to our democracy,” explains Josh Silver, who heads the nonpartisan reform group RepresentUs. “Gerrymandering is one of the worst forms of political corruption, and leads to extremism and partisan gridlock. The maps drawn this year will shape American politics and policy for the next decade.”

The best scenario for American democracy would have been for Senate Democrats to scrap the filibuster and enact the For the People Act before Thursday’s release of the Census data. That legislation seeks to ban partisan gerrymandering and strengthen the position of advocates for communities of color in the redistricting process. “It would also,” notes the Brennan Center for Justice, “enhance the ability of voters to challenge racially or politically discriminatory maps in court, require meaningful transparency in the map-drawing process, and mandate the use of independent commissions to draw maps.”

When senators failed to pass the For the People Act before the August recess, they left an opening for partisans to warp district lines in the 35 states where maps will be drawn by legislators, as opposed to nonpartisan commissions. That gives Republicans a substantial advantage. As Drew DeSilver of the Pew Research Center reminds us, “Republicans will drive that process in 20 states, versus 11 for Democrats.” In four states, divided government makes it most likely that the final decision could be made in the state courts.

Republicans are in full control of states that will be adding seats based on patterns of population growth confirmed by the Census data, such as Texas and Florida. They also control several large states, such as Georgia, where seats will not be added but where a redrawing of lines could be used to tip existing seats to the GOP candidates. In contrast, a number of states where Democrats are in charge, such as New York and Illinois, will lose congressional seats. So, too, will heavily Democratic California, where lines are drawn by a nonpartisan commission.

More than personalities, more than money, more than ideology or ideas, gerrymandering determines which party wins elections. “Most Americans believe that who wins political races is decided on election day by the voters. But in a single-member district electoral system that is frequently not true. Who wins is often determined before voters even go to the polls—sometimes many years before,” explains political scientist Douglas Amy, an expert on electoral systems at Mount Holyoke College. “The outcome is decided by those who draw the district lines. If they decide to create a district that is 70 percent Republican, there is little chance the Democratic candidate will win. And Republican candidates will usually lose if a district is drawn so that it is predominantly Democratic. Voters go to the polls confident in the illusion that they control the fate of the candidates. But in reality they are often only participating in the last act of political play whose ending has already been written.”

An analysis by The Cook Political Report, based on the initial round of Census data released earlier this year, determined that Democrats will control the line-drawing process for 75 seats, while Republicans will have the upper hand when it comes to creating 187 seats.

This has led some analysts to suggest that end result of the redistricting processes based on the latest numbers could see Republicans gain as many as seven seats. That’s a daunting number, as House Speaker Nancy Pelosi’s Democrats currently enjoy only a 220-212 majority, with three vacancies. “Republicans’ biggest redistricting weapons are Texas, Florida, Georgia and North Carolina—and they could conceivably pick up all five seats they need for the majority from those four alone,” explains Cook’s David Wasserman.

That’s not guaranteed, of course. Democrat’s prospects might be improved by favorable maps from states such as Maryland and Illinois. But there are also scenarios where things could go even worse for the party.

That’s because of the role of the courts in some states where Democrats control the governorship but not the legislature. In Wisconsin, for instance, Democratic Governor Tony Evers would certainly reject a gerrymandered map produced by the state’s Republican-controlled legislature. But a standoff could put the final decision in the hands of the state Supreme Court, which is controlled by a conservative majority that regularly sides with the GOP.

The coming weeks will be perilous. While it is true that Republicans and Democrats have all been guilty of engaging in partisan gerrymandering over the years, Republicans have a clear advantage in this moment. And they have displayed far greater determination to use whatever opportunities they are handed to advance an ambitious voter suppression strategy.

For those who do not want to see control of the House shift, the last weeks of August and the first weeks of September will be critical. Democratic legislators and responsible Republicans, along with grassroots activists, must do everything in their power to prevent hyper-partisan Republicans legislators from approving gerrymandered maps without adequate public input and debate. They also must put pressure on Democratic US senators to recognize what is at stake, and to use their majority to get the Senate to act on the For the People Act when it returns to Washington after Labor Day.

After Republicans took advantage of the chamber’s archaic filibuster power to block attempts to address voting rights issues before the recess, Senate majority leader Chuck Schumer said, “Republicans refusing to support anything on voting rights is not an excuse for Democrats to do nothing.”

Schumer recognizes the threat. “Partisan gerrymandering,” he explained Wednesday, “strips the American people of their right to have a truly representative government. Voters ought to pick their politicians, not the other way around. But in so many states, partisan legislators draw maps that artificially maximize the number of seats that the majority party will win. Some districts are so safe that the most extreme candidates can run and win with hardly any competition.”

The majority leader’s assessment of the threat is spot on. But identifying the problem is not enough. To address the threat, the filibuster must be eliminated—or, at the least, dispensed with when considering democracy initiatives. “With the Census redistricting data released, we are now up against an urgent, ticking time bomb before we can no longer save our democracy,” says the Sunrise Movement’s Ellen Sciales. “Now, right before the states can begin redistricting, is the last shot Democrats have to save representative democracy as we know it.”

This is the truth every Democratic senator needs to recognize during this recess. If they don’t, the chances that they will be sharing power in 2023 with a Republican-controlled House will increase exponentially.