DES MOINES — President Trump’s Midwest is the key gubernatorial battleground in 2018. The swath of states that secured the president’s electoral college victory in 2016 is now home to a series of statehouse contests that could alter the balance of power in a region of the country long crucial to presidential elections.

The stakes are sizable as the two parties intensify their efforts heading into fall campaigning. Democratic victories in the Midwest not only could give the party’s presidential nominee needed help in the 2020 election but also would provide Democrats with new leverage in the critical redistricting battles that will take place after the 2020 Census.

The Midwest secured Trump’s victory in 2016. He carried Iowa and Ohio by surprisingly comfortable margins. He won Wisconsin, Michigan and Pennsylvania each by less than a percentage point. He narrowly lost Minnesota and fell well short in Illinois. Republicans control the governor’s mansions in all of those states except Minnesota and Pennsylvania, and all of them will elect governors in November.

Women of color candidates see the 2018 midterms as an opportunity to challenge the status quo and break down barriers. (Alice Li, Sarah Hashemi, Kayla Epstein/The Washington Post)

Today just about everything is in play gubernatorially. The Cook Political Report puts Iowa, Michigan and Ohio in the toss-up category, leans Wisconsin toward the GOP and leans Illinois and Minnesota toward the Democrats. The one exception is Pennsylvania: Democratic Gov. Tom Wolf, who played a key role in forcing the drawing of new congressional district lines that are likely to give his party additional House seats in the next Congress, is rated to be in good shape for reelection.

And then there is Kansas, which Trump carried by 21 points. That state too is listed among the toss-ups, because the Republicans just concluded a contentious primary battle that saw incumbent Gov. Jeff Colyer, the establishment favorite, lose to Secretary of State Kris Kobach.

Kansas will be a reach for Democrats; few are counting on it. But Kobach, a Trump ally who led the flawed commission tasked with investigating Trump’s unproven claims of voter fraud, carries baggage and a divided party into the general election.

Iowa is a case in point for the state of play in the Midwest. Trump won Iowa by nine points, after former president Barack Obama won it by 10 points in 2008 and by six points in 2012. The shift in the margin of victory between 2012 and 2016 was one of the biggest in the nation. More than 30 of Iowa’s 99 counties flipped from Democrat to Republican between 2012 and 2016.

A year ago, Democratic and Republican strategists gave the advantage in the governor’s race to newly elevated Republican Gov. Kim Reynolds, who as lieutenant governor succeeded long-serving Terry Branstad after he was nominated as U.S. ambassador to China. Today, Democrats are cautiously optimistic and Republicans admittedly nervous. “I think what this election is going to show is that Iowa is a purple state,” said Troy Price, the Iowa Democratic Party chair.

Reynolds should benefit from Iowa’s generally healthy economy and low unemployment rate. GOP strategists say her biography as a product of rural Iowa and working-class roots will play well with voters, and she will contrast her background with that of the Democratic nominee, wealthy businessman Fred Hubbell.

Her challenges, meanwhile, come from various directions. She inherited the governorship and now has to run on her own in a midterm election year in which the party in the White House is historically at a disadvantage.

Her administration has come under fire for its management of the Medicaid program. The Iowa legislature approved a highly restrictive abortion law (now tied up in the courts) that gives Democrats a way to appeal to some suburban female voters. Beyond that, Trump’s trade policies could sour Iowa farmers, although even some Democrats say right now it’s more of a “slow-burn issue” rather than one dominating the campaign.

At the time of Trump’s victory, there were questions about whether Iowa was moving from being a purple state to one closer to red. Today, Republicans have a more realistic perspective: that 2016 was a perfect storm, conditions that won’t exist this November.

They see that Trump was able to bring out voters who had not embraced the GOP in recent presidential elections and whose support might not be transferrable. Meanwhile, they know that Hillary Clinton was a demonstrably weak candidate in Iowa and in some other Midwest states. “The whole upper Mississippi Valley revolted against her,” said David Kochel, a Republican strategist advising Reynolds.

Democrats and Republicans alike note that going into November, the energy is considerably stronger on the left than the right. Republicans will look to insulate their gubernatorial candidates from national winds by focusing on state-specific issues. But that’s difficult, particularly in an environment in which the president so dominates everything politically.

Hubbell, the Democratic nominee, will have a fight on his hands. He is a temperate personality, not exactly the profile of a hard charger who could, by himself, energize the party’s base. But with two highly competitive GOP-held House races also on the ballot, Democrats will have plenty of incentives to turn out. The gubernatorial contest seems destined to remain close to the end.

The most vulnerable GOP-held seat is in Illinois, where wealthy Republican Gov. Bruce Rauner is the clear underdog against wealthy Democratic challenger J.B. Pritzker. Meanwhile, Minnesota Democrats are bullish about the prospects for Rep. Tim Walz (D) to succeed Gov. Mark Dayton (D) in the governor’s mansion, after former Republican governor Tim Pawlenty, the favorite of national GOP leaders, lost the primary to Hennepin County Commissioner Jeff Johnson.

Among the other GOP-held seats, Democrats feel more confident about Michigan than they do about Iowa, Wisconsin or Ohio. In Michigan, Democratic state Sen. Gretchen Whitmer survived a primary challenge from the left and now faces GOP attorney general Bill Schuette in the contest to succeed term-limited Gov. Rick Snyder (R).

Ohio has a history of disappointing Democratic statewide candidates, and that could be the case again this year. But with Republican Gov. John Kasich leaving because of term limits and Democratic Sen. Sherrod Brown on the ballot and favored, the open-seat race for governor between Republican Mike DeWine and Democrat Richard Cordray is genuinely competitive.

That leaves Wisconsin. Gov. Scott Walker (R) has never had easy races and remains as polarizing a figure as he’s been since the uproar over collective bargaining that he created early in his first term. He survived a recall election in 2012 and won reelection in 2014. The most recent Marquette Law School poll shows the race tied. Other recent polls have given an edge to Democrat Tony Evers. Walker’s first two elections came in good years for Republicans. His bid for a third term comes in a year favorable to Democrats.

It’s possible, though not probable, that by the day after the election in November, Democrats will control most of the governorships in a band of states stretching from Kansas to Pennsylvania. Don’t count on that clean sweep, but it’s clear that the region that broke many Democrats’ hearts on election night 2016 could be a bright spot for the party this November.