TOLEDO, Ohio (Reuters) - Two years ago, Ohio and other states in the former industrial heartlands of the Great Lakes region catapulted Donald Trump into the White House.

Today, in the final stretch to November’s congressional elections, they are showing that Trumpism has its limits as Democrats make surprising gains in races across the region, according to opinion polls.

Last week, Democratic gubernatorial candidate Richard Cordray, often described as a liberal “progressive populist,” campaigned in working-class Toledo in a race that has remained tight with election day just two weeks away -- a sign of a resurgence in his party in Ohio.

“We will change this state for the better. We will change this nation for the better,” Cordray told a room of black voters in downtown Toledo on Thursday. “2018 leads to 2020.”

A poll released this month by Suffolk University showed Cordray with a six-point lead, although other polls have showed the race to be essentially a toss-up.

Not only is Cordray, the former head of the Consumer Financial Protection Bureau who has long been vilified by Republicans as an anti-business zealot, staying neck-and-neck with his opponent, Mike DeWine, but U.S. Senator Sherrod Brown, a Democrat, is on track to keep his Ohio seat in his race against Trump-backed candidate Jim Renacci.

That pattern is playing out in other states in the Great Lakes region that Trump won in 2016, where Democratic Senate and gubernatorial candidates are either convincingly ahead of their Republican opponents or, like Cordray, beating expectations and holding their own.

It suggests that Republican hopes that Trump had transformed the industrial Midwest into friendly ground may have been misplaced. Beyond the Nov. 6 elections, which will decide which party controls the Senate and the U.S. House of Representatives, that has ramifications for Trump’s reelection bid in 2020.

The reasons why Democrats now have an edge in these states are complex and go beyond Trump’s standing, party sources and analysts say. It is a mix of historical midterm election trends, well-known Democratic candidates with reliable constituencies facing weaker Republican opponents, enthusiasm among Democratic voters, deepening concerns on issues such as healthcare, and yes, some push-back against the president.

“Folks are just sick and tired of him. It’s too much,” said Joe Zepecki, a Democratic strategist in Wisconsin. “It’s the Trump show all the time. And that is not helping Republican candidates.”

A Republican source familiar with the party’s thinking, however, said the problem lies more with Trump himself not being on the ballot, which has left many of his supporters in these states either disengaged or willing to consider supporting Democrats.

“If it’s not Trump, they’re not going to pull the R lever just because it’s the same party of the president,” the source said.

Democrats need to pick up a net total of two seats to take control of the Senate and 23 seats to assume control of the House, which is considered more likely by election handicappers. Taking either chamber would stymie much of Trump’s agenda.

CHANGE OF SEASON

After Trump’s surprise victory in 2016, the thinking was that perhaps Democrats had lost touch with their traditional middle-class supporters in this “Rust Belt” region. Republicans looked to capitalize and tighten their grip on power.

But that has never materialized.

Beyond Ohio, in next-door Pennsylvania, Democratic governor Tom Wolf is comfortably ahead of his challenger, Scott Wagner, who aired a shocking TV ad threatening to stomp Wolf’s face with “golf spikes” in a last-minute effort to spark his campaign.

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The U.S. Senate race there, featuring incumbent Democrat Bob Casey against U.S. Representative Lou Barletta, another Trump favorite, has long considered to be over in Casey’s favor.

In Michigan, Democratic Senator Debbie Stabenow never faced a serious threat from her Trump-supported opponent, John James. And Democrat Gretchen Whitmer has held a steady lead in the governor’s race over Republican Bill Schuette.

In Wisconsin, where Trump’s presidential victory in 2016 marked the first by a Republican in the state since 1984, Republican Governor Scott Walker is in the fight of his political life against his Democratic challenger Tony Evers, while the state’s Republican Senate candidate Leah Vukmir is badly trailing Democratic Senator Tammy Baldwin in a race that was widely expected to be competitive.

A poll this month by Marquette University showed Evers and Walker tied. The same poll gave Baldwin a 10-point lead in the Senate race.

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Trump’s efforts appear to have done little to boost the prospects of the candidates he has endorsed, despite his multiple trips to the region and his promises that renegotiated trade deals with Canada and Mexico and strong tariffs will bring jobs back to the Rust Belt.

Despite that push, unions such as the AFL-CIO have been heavily involved in the region’s races, encouraging members to back Democratic candidates and mobilizing voters, hoping to avoid a repeat of 2016 when many members defected to Trump, said Julie Greene, director of mobilization for the union.

Trump’s hold in the Great Lakes has never been as strong as he has claimed. While he took Ohio by 445,000 votes, he won Michigan, Pennsylvania and Wisconsin, with their combined 46 electoral votes, by less than 1 percentage point, or by total of just about 80,000 votes. He can afford little slippage in the region when he runs for reelection.

HEALTHCARE FOCUS

Capturing governorships and statehouses has been a longstanding goal of the Democratic Party with the next U.S. census approaching in 2020. States will use the results to redraw congressional districts, a process that was dominated by Republicans in 2010.

Democratic officials and strategists believe healthcare and specifically, former President Barack Obama’s Affordable Care Act, once a political liability, have become a difference-making issue.

Candidates such as Cordray and Evers have centered much of their campaigns around the act’s protection of preexisting medical conditions and its expansion of Medicaid. All four Trump states have been hit heavily by the opioid epidemic.

That’s put Republicans, who largely resisted what they call “Obamacare,” in a bind.

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A poll released last week by the Kaiser Family Foundation listed healthcare as the top voting issue for Democrats and independents, particularly among women voters.

Walker in Wisconsin and DeWine in Ohio both at times have backed efforts to repeal the act or challenge it in court. But both candidates say they have always favored coverage for preexisting conditions in some form.

Success in congressional midterm elections has been an unreliable indicator for the following presidential election. For example, after a Republican wave in 2010 resulted in that party taking the House, Obama was reelected two years later.

That is why Steve Mitchell, a Republican pollster in Michigan, warned that Democrats should not underestimate Trump’s strength in the region.

A presidential election, he said, “is a whole different animal.”

(State of Play is a weekly examination by Reuters political correspondent James Oliphant on the key races, players and issues in the run-up to U.S. congressional elections in November that will determine which party controls Congress)