Donald Trump’s recent plunge in the polls has tempted Democrats to widen their dreams for a big night in November. A landslide victory for Hillary Clinton, they now believe, could bring with it control of the U.S. Senate and dramatically shrink the party’s gap with Republicans in the House—if not flip it entirely.

But there could be a Trump effect in another 2016 battleground that could shape the electoral landscape much further into the future: the elections for control of state legislatures.

The wave elections of 2010 and 2014 that gave Republicans majorities in Congress also handed them the levers of power in state governments across the country. Thirty-one out of the nation’s 50 governors are Republicans, and the GOP now controls a record 69 out of 99 state legislative chambers. The gains the party made in 2010 were particularly crucial, as they allowed Republicans to dominate the redistricting process that occurred after the decennial Census in a way that locked in their gains in the U.S. House and local legislative districts in states where they had won majorities.

Both parties had expected Democrats to make up some ground in 2016 for two reasons. They have typically performed better up and down the ballot in presidential-election years, and with Republicans at an all-time high, Democrats had little place to go besides up.

Yet Trump’s name atop the GOP ticket has prompted Democrats and their allies to set their sights higher for state legislative races this fall. With more states in play, they are now aiming to flip at least 10 and as many as 13 legislative chambers. Those victories could give Democrats complete control of the governments in Colorado, Minnesota, and Washington state while breaking the GOP’s one-party rule in Michigan, Maine, and even Florida—all places where Republicans had made gains during the Obama era. “The expanding map that you see on the national level reflects what we see on the state level,” said Jessica Post, executive director of the Democratic Legislative Campaign Committee. “We thought that no matter who the presidential nominee was, we thought we had an excellent shot at winning back the Minnesota House, winning back the New Mexico House, for example. But now we’re also looking back and saying, wow, Trump in the public polling is at 36 percent in Michigan.”

“I think it’s put some additional states into play, and it’s also put a lot of additional districts in play,” Post told me in an interview this week.

In Colorado, with a Democratic governor and a majority in the state House of Representatives, Democrats need to flip just one seat in the Senate to regain full control of the government. Republicans had narrowly captured the Senate majority in 2014. But an increase in Latino voters in recent years has made the one-time GOP stronghold nearly out of reach for the Trump campaign, giving Democrats confidence they can use a Clinton victory to capture down-ballot seats. Democrats need to gain seven seats to capture the Minnesota state House and just three in New Mexico. Both chambers in Washington state are in play—Democrats have a two-seat advantage in the House and Republicans are up by one in the Senate—but Democrats are again hopeful that a likely Clinton win there will swing the legislature toward them.

The Flint water crisis in Michigan and the GOP-controlled legislature’s passage of a widely criticized anti-transgender bathroom law in North Carolina have left Democrats optimistic about bigger-than-expected gains in those states as well. And then there are states like Pennsylvania, Florida, and Arizona, where Democrats are rethinking their assumptions about how long it would take them to wrest legislative chambers from the GOP’s control. Post pointed to a surge in Latino voter registrations in Florida and Arizona along with an apparent nosedive in Trump’s support in the Philadelphia suburbs as factors that Democrats could exploit. “We started this cycle saying, ‘Let’s just chip away at these large legislative majorities,” she told me. “Now we’re saying we can take big cuts at these majorities and see if we can run this all the way over the finish line.”

After record gains in the last several years, the GOP knew it was in for “a stiff challenge” this fall, in the words of Matt Walter, president of the Republican State Leadership Committee. Republicans still have a few more chambers they can flip. There’s the Kentucky House, one of the final Democratic bastions in the South. And they have a shot to take the state Senate in Connecticut, where the unpopularity of Governor Dannel Malloy could be a drag on Democratic candidates. But mostly they will be trying to defend the majorities they have recently claimed, particularly in the blue and purple states surrounding the Great Lakes.

Like many Republican officials these days, Walter was none too eager to discuss Trump’s candidacy or the impact it might have on the party’s down-ballot candidates. When I asked him if the GOP would stand a better chance of holding onto their state legislative majorities if the party had picked someone else as its presidential nominee, Walter simply replied: “That’s not the reality we live in.”

The GOP is urging its candidates to ignore the national environment as much as possible and focus on local issues—an approach that parties with an unpopular leader have tried, with little apparent success, for decades. “Our advice to our candidates is always to run your own race, not to get distracted by other races, other environmental factors that are beyond your control,” Walter said.

The issues that animate state legislative campaigns are naturally different from those that dominate the presidential election, but historically, “the top of the ticket in the presidential race does tend to have coattails in the legislatures,” said Louis Jacobson, who handicaps legislative elections for Governing Magazine and is a co-author of the 2016 Almanac of American Politics. “But,” he added, “this is a quirky enough political year that I think you have to be more cautious.”

If Trump does not reverse his slide in the polls, Republicans could decide to redirect resources in an effort to save their majorities in Congress and the state legislatures. And they are banking on voters choosing to split their ticket even if they can’t support Trump for president. Walter pointed to a recent Gallup finding that voters felt considerably more favorable about their local governments than the federal government—a result that could benefit Republican incumbents at the state level. “Many more of the impactful decision governments makes in people’s lives are happening in the state capitals, and they’re happening in their localities. They’re not happening in far-off Washington, D.C.,” Walter said. “What we’re seeing as a long-term trend is a greater understanding, a greater appreciation, greater respect for the government closest to the people.”

The stakes for control of state governments are all the higher because unlike Congress, legislatures outside Washington have been hotbeds of activity rather than gridlock. Republicans have used their power in North Carolina, Texas, Wisconsin, and Ohio to pass strict voter-ID laws (some of which have been challenged or halted by the courts) and in some states have chosen to block expansions of Medicaid under Obamacare. Democrats say that victories in November could allow them to raise the minimum wage and enact automatic voter registration in additional states, and approve measures to mandate equal pay for women, combat climate change, and tighten gun-control laws. And if they can break up one-party Republican rule in other states, they can stop conservatives from passing so-called “pre-emption bills” that restrict progressive city governments from taking action on those issues.

Yet even now, the focus for both parties at the state level is as much about 2020 as it is about 2017. In states without independent redistricting commissions, the state legislatures draw the maps both for their own seats and the U.S. House. Democrats have already launched multi-election efforts to win back legislative chambers by 2020, and on Wednesday, EMILY’s List—an allied group backing women candidates—unveiled their own to help Democrats in 14 states over the next five years.

The elections this year won’t be determinative. Even if Clinton wins decisively and Democrats make strong gains, they could still face a tough midterm election in 2018, when Republicans are traditionally stronger and the party in the White House often loses seats. But as Post noted, “incumbency matters.” To have any chance at setting themselves up for 2020, Democrats need Clinton’s coattails to extend far down the ballot this year. “All signs point to the pendulum swinging back in their direction,” said Tim Storey, an elections analyst at the National Conference of State Legislatures. “It’s difficult to know if it will be substantial enough—a tidal wave or a landslide or any of that business. That is still too early to know.”