A sign supporting President Trump stands in the front yard of a house in Crown City, Ohio. Decline in support from blue-collar white women in the state is among the steepest anywhere in the country.Brian Snyder / Reuters

A massive new measure of state-by-state attitudes toward Donald Trump offers important clues about the pressure points that could tip the 2018 elections.

Last week, Gallup released Trump’s average approval rating in all 50 states in 2017, based on more than 171,000 survey interviews it conducted over the course of the year. That compilation put Trump’s average national approval rating for 2017 at 38 percent, close to the 40 percent Gallup recorded for him in its latest weekly finding.

Throughout the year, Gallup found Trump averaged majority approval in just 12 states; in nine states that he carried in 2016, he managed an approval rating of 43 percent or less. New Hampshire and Nevada—both at 42 percent—were the only two of the 20 states Hillary Clinton carried where Trump’s approval rating peeked above 37 percent.

To better illuminate patterns of Trump’s strengths and weaknesses, Gallup provided The Atlantic with more finely grained demographic results in 13 battleground states where there were enough interviews to analyze his ratings in detail: six across the Rustbelt (Pennsylvania, Ohio, Michigan, Iowa, Wisconsin, and Minnesota) and seven through the Sunbelt (Virginia, North Carolina, Georgia, Florida, Texas, Arizona, and Colorado). These findings underscore both the persistence of the demographic divides over Trump—and the continuing tug of regional variations. With congressional elections increasingly pivoting on voter attitudes toward the president, both dynamics will frame the battle for control of Congress this fall.

Unlike a comparable compilation of 2017 surveys from the online-polling firm SurveyMonkey, which found some gains for Trump with non-white voters, the Gallup data show Trump still failed to make inroads with them. In none of the 13 states did more than 23 percent of minorities say they approve of Trump’s performance last year.

Among whites, the results show the persistent power of both class and gender in driving the reaction to him. In all 13 states, white men and women with a college degree gave Trump a lower approval rating than their counterparts without degrees. But in each state, Trump’s approval rating was also considerably lower among white women than white men at the same level of education.

These twin forces—of class and gender—have established a sharp continuum of white attitudes toward Trump. White men without a college degree remain his foundation, even if the pillar is showing some cracks: Relative to his 2016 vote, Trump’s approval rating in 2017 among this group declined in all 13 states. But given his commanding initial position, Trump retains a very strong hold on those men, drawing 60 percent or more approval from them in each state except Michigan, Colorado, and Minnesota (though he still retains majority support in those).

At the opposite pole, college-educated women remain the engine of white resistance to Trump. In only four of the 13 states (more on them below) did Trump’s approval among college-educated white women exceed an anemic 34 percent. That widespread rejection of Trump keys the Democratic opportunity in 2018 in House seats in information-age, white-collar suburbs in major metropolitan areas.

The two other groups of whites are more conflicted. Among college-educated white men, Trump retains majority approval in five of the states and draws at least 45 percent in four more. The intense backlash against Trump from well-educated white women means that GOP hopes of minimizing their suburban losses may depend on maintaining majority support from college-educated white men—who many Republican strategists consider the audience most likely to snap back to GOP candidates over the tax bill and generally brightening economic picture (the stock market’s tumble this week notwithstanding).

The situation looks even more volatile among white women without a college degree. No group was more central to Trump’s victory, especially in the Rustbelt states that effectively decided the election. (Trump won at least 56 percent of those women in Ohio, Wisconsin, Michigan, and Pennsylvania, according to exit polls.) In 2017, Gallup found, Trump averaged majority approval from these blue-collar white women in six of the 13 states. But that finding highlights the continuing force of regional variation in shaping attitudes about Trump: All six of those states are in the South and Southwest.

In the Rustbelt states that decided 2016, Trump has slipped into a much more precarious position with these women: Gallup put his 2017 approval with them at 45 percent in Pennsylvania, 42 percent in Michigan, and 39 percent or less in Minnesota, Iowa, Ohio, and Wisconsin. Compared to his 2016 vote, his 2017 approval among blue-collar white women in the Rustbelt represented some of his largest declines anywhere—18 percentage points in Ohio and 19 in Wisconsin and Minnesota. That erosion, which intensified during Trump’s effort to repeal the Affordable Care Act, creates the opening for Democrats to contest blue-collar and non-urban House seats this fall through the Midwest and Northeast.

Conversely, Trump’s relatively greater strength among Sunbelt college-educated whites underscores the challenge Democrats face extending the battlefield into the white-collar Republican-held House seats they hope to flip in suburbs of Atlanta, Houston, and Dallas. Though he’s slipped substantially relative to his 2016 vote among college-educated white women and men alike in Georgia and Texas, they remain Trump’s two best states with those groups. (Along with Arizona and Florida, they were the only states where Trump draws positive approval ratings from more than about one-in-three white women with a college degree.)

Gallup’s findings on Trump clarify the hurdles Democrats must clear to recapture the House. Job one is generating strong turnout from the minorities and young people most alienated from him in all polls. Beyond that, these numbers suggest Democrats must solve two intertwined demographic and geographic puzzles by winning more blue-collar women in the Rustbelt and more white-collar whites in the Sunbelt. Trump’s tumultuous tenure has provided them an opening with those voters—but no guarantees of pushing through it.

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