Rep. Peter J. Roskam (R-Ill.) at Elkay Manufacturing near Downers Grove, Ill., on Monday. (Ashlee Rezin/Chicago Sun-Times/AP)
Opinion writer

Republican Rep. Peter J. Roskam’s reelection campaign has taken him to a conference room at the headquarters here of Elkay Manufacturing, maker of sinks, faucets and kitchen cabinets.

An Elkay executive tells Roskam that the GOP tax cut has enabled the company to increase investment and give workers a bonus. Still, it is difficult to find help in a tight labor market where many young people shun factory employment. Elkay has to work with schools, businesses and community groups to train and motivate a future workforce. “It takes a village,” the executive remarks, as Roskam nods.

Later, Roskam laughs as he acknowledges having quietly tolerated his constituent’s invocation of a catchphrase associated with Democrat Hillary Clinton. “Why antagonize?” he says.

That summarizes Roskam’s political predicament as he tries to secure a seventh term in Illinois’s 6th Congressional District, which sprawls like a giant letter “C” across the affluent suburbs west of Chicago.

A bastion of genteel “country-club Republicanism” — the median household earned nearly $100,000 in 2017; there are 19 golf courses within the district’s largest county, DuPage — the 6th District has been sending GOP representatives to Washington since 1972. Most of that time, it was pro-life icon Henry J. Hyde, until Hyde retired and Roskam won a race to succeed him in 2006.

In 2016, however, the district reelected Roskam while preferring Clinton by seven points over Donald Trump for president, one of 23 districts nationally that split its vote between her and a GOP House candidate. That instantly made the district a 2018 Democratic target. Team Blue has spent millions on behalf of nominee Sean Casten, a clean-energy entrepreneur making his first bid for public office.

The Democratic push in the 6th District is part of a nationwide strategy to flip suburban House districts from red to blue, on the assumption that moral revulsion to Trump will outweigh material prosperity among well-educated, upscale voters.

There are relatively few white men without a college education, Trump’s core constituency, in the 6th District. It is about 80 percent white, but 54 percent of adults have a college degree, and 21 percent have advanced degrees.

In the age of Trump, a lot of these people may be about to become country-club Democrats.

Six GOP House members from districts Clinton won in 2016 retired rather than swim upstream in 2018. Roskam, though, is hoping his business-friendly constituents will reward him for the 2017 tax-cut legislation, of which he was an architect.

He is also banking on the 6th District’s imperviousness to previous blue waves: Hyde won his first term in 1974, the Watergate year when Democrats gained 49 seats; Roskam’s first victory came in 2006, when Democrats rode a backlash against President George W. Bush and the Iraq War to a 31-seat pickup.

Polls suggest the race between Roskam and Casten is the closest thing to a pure toss-up in the country. Democratic enthusiasm is high. Among the 15 volunteers who showed up on a cold, rainy Sunday to canvass door-to-door for Casten in the town of Elgin recently was Bill Wentz, a 73-year-old lawyer who epitomizes the district’s demographic. He voted for Roskam in the past but has all but had it with the GOP, and he says many of his friends have, too.

“Basically, the problem is Trump and the Trump administration,” he says.

Casten says he was motivated to challenge Roskam after a meeting at the congressman’s office in 2016, during which the Republican dismissed his ideas for a clean-energy tax credit. Climate change is “my North Star,” Casten told me, though for the time being his campaign is emphasizing poll-tested Democratic themes such as health coverage for preexisting conditions.

“This a pretty moral-value-heavy district,” Casten says. “There’s a certain sense of noblesse oblige, and to whom much is given, much is expected.” But there is no denying the 6th District is rich: Casten is trying to turn Roskam’s support for last year’s tax bill against him by pointing out that its limitation on deducting state and local taxes may hurt upper-middle-class people in high-tax Illinois.

Roskam’s closing argument amounts to acknowledging tacitly that Trump is a huge liability for him — and trying to flip the script. Seizing on some of Casten’s more intemperate statements (the challenger once likened Trump to Osama bin Laden), Roskam accuses the Democrat of “emulating” Trump.

“Civility is on the ballot Nov. 6,” Roskam told a recent news conference.

Casten calls that hypocrisy, saying Roskam has failed to sufficiently call out the president. “There’s a certain amount of gaslighting going on,” Casten says, “and he’s not the only one.”

Born and raised in the 6th District, and known more for his supply-side policy wonkery than for his rhetoric, Roskam has to hope he is one of the few Republicans who can pull off this particular act of jujitsu.

If he can’t, the GOP is probably in for a long night next Tuesday and may be facing many future defeats in its erstwhile suburban strongholds.

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