Compounding that risk for Republicans is that Democrats are nominating a historic number of female candidates precisely as Trump is pushing so many white-collar women away from the GOP. Democrats have chosen women in more than 40 percent of the 367 districts where they have already selected nominees this year, according to the Center for American Women and Politics at Rutgers University. (Women represent only about 13 percent of Republican nominees so far.)

“There may be a permanent partisan shift among those college-educated women,” says the Democratic pollster Anna Greenberg. “In 2006 and 2008, we picked up [House] seats we shouldn’t have and they later reverted back [to Republicans]. I think some of the seats we pick up [this year] are going to stay, because the margins among women are going to stay.”

The prospects for Democrats with blue-collar white women are much more uncertain, though. Those women were crucial to Trump’s victory in 2016, particularly in the pivotal states across the Rust Belt. Trump significantly expanded on Mitt Romney’s margins in 2012 among those women in Iowa, Ohio, Michigan, Wisconsin, and Pennsylvania. In the latter three states, which effectively decided the race, Trump ran at least 13 points better among white women without a college degree than those with one. It’s no exaggeration to say the principal reason the first female major-party nominee failed to win the presidency is because so many working-class white women in the Rust Belt rejected her.

The GOP is doubling down on its older white base—and hoping the more diverse Millennials don’t show up to the polls

Trump has suffered some erosion with these non–college-educated white women, but they don’t display nearly as much resistance to him as their college-educated counterparts. On a wide variety of questions, they divide closely over Trump. About half of them say they consider him a racist or are embarrassed by his behavior, and slightly more than half say they don’t believe he respects women as much as men. In this week’s Quinnipiac poll, they split exactly in half on whether they like Trump’s policies and broke closely over his job performance (51 percent positive to 44 percent negative).

Some surveys have shown these women souring on Trump in greater numbers across the big midwestern battlegrounds, such as Michigan, Wisconsin, and Minnesota. But overall, most polls still mostly show them leaning solidly toward the GOP in the congressional contest—though generally by smaller margins than in House elections since 2010. Quinnipiac’s latest survey gave the GOP a nine-point edge among them.

Brabender says that while some blue-collar white women have grown uneasy over Trump’s confrontational style, that’s outweighed by their satisfaction with his results. Greenberg agrees it remains a heavy lift to move large numbers of blue-collar white women, especially older ones resistant to demographic and cultural change, toward Democrats. But she says their unease over Trump’s behavior may cause many of them to simply sit out November. “It is so offensive, and they just don’t understand why he thinks he needs to do that,” she says. “It is less of a conversion to Democrats, and, for better or worse, it turns them off about politics more generally and it leads them to lower participation.”