As in 2018, health care ranks among Trump's 2020 challenges (POLL) The key issue of the 2018 midterms may trouble Donald Trump in 2020.

The key issue of the 2018 midterms may stick around to trouble President Donald Trump in 2020: Americans, by a 17-point margin, say his handling of health care makes them more likely to oppose than support him for a second term.

That result, from the latest ABC News/Washington Post poll, marks one of many challenges Trump is expected to face as he seeks re-election.

The Mueller report and his immigration policies are substantial negatives as well. As reported Friday, Trump’s overall popularity is low: just 39 % of people approve of his work in office, and 55% flatly rule out voting for him next year.

See PDF for full results, charts and tables.

Beyond that, a remarkable 75% of Americans, and 85% of registered voters, say they’re certain to vote in the 2020 election -- intended turnout levels typically only seen in the closing days of a presidential contest. If that intensity is maintained, it may boost Democratic candidates, many of whose core support groups are less reliable voters.

But even as Trump faces bigger-than-typical risks for a president seeking re-election, 2020 may not be as much of a slam-dunk for the Democrats as some of his ratings would suggest. One example: Among those who rule Trump out, just 29% say they’ll definitely support his eventual Democratic opponent. Two-thirds say they’re waiting to see who that is.

While more than half of people say they definitely won’t support Trump, 42% of Americans overall, and 45% of registered voters, say they’d at least consider him for a second term. Trump won 46.1% of the popular vote compared to Hillary Clinton’s 48.2% in 2016, demonstrating that losing the popular vote is irrelevant if you win the Electoral College.

Willingness to consider Trump for a second term varies markedly among groups in this poll, produced for ABC by Langer Research Associates. In the Midwest -- the region he mostly won in 2016 -- 54% say they’d definitely or possibly support him for re-election. So do 54% of white people nationally, and 58% in rural areas where his support is strongest.

Trump’s weaknesses are apparent in these results as well: In his own party, 15% of Republicans say they definitely will not support Trump for-election, as do 30% of people who identify as conservative.

Among other groups, this soars to 61% of 18- to 39-year-olds, 62% of women, 64% of those with a postgraduate degree, 68% of urban residents, 81% of Hispanics and 86% of blacks.

Approval and issues

Overall approval may be chief among Trump’s challenges. He’s averaged just a 38% approval rating since he took office, the lowest by far for any president in his first 2 1/4 years in office in surveys dating back to Harry Truman’s administration more than 70 years ago.

Truman overcame a recession-fueled 40% approval rating in June 1948 to win re-election five months later. One difference, though, is that Truman saw much higher approval scores, averaging 56% -- 18 percentage points better than Trump -- in his first 2 1/4 years. Trump’s never exceeded 42% approval.

Other factors add to the president’s challenges:

• Of people polled, 40% say his handling of health care makes them more likely to oppose him for re-election, while 23% say it makes them more likely to support him. Voters in the 2018 midterms selected health care as the top issue in their vote by a wide margin over three others offered, and those who picked it favored Democrats for Congress by a margin of 75 to 23%.

Trump’s response to the importance of the issue is worth watching; he said on April 1 that a GOP vote on a health care reform plan would be put off until after the election.

• Based on his handling of immigration policy, 44% of people say they’re more likely to oppose Trump for a second term, versus 31% more likely to support him, a 13-point net negative.

• The Mueller report produces a 22-point net negative score for Trump: 36% say it makes them more likely to oppose him for re-election, versus just 14% more likely to support him. As reported Friday, 58% think Trump lied to the public about the Mueller investigation.

Trump’s score on handling international trade is closer -- Americans by a net of 5 percentage points say it makes them more likely to oppose him for re-election. He also has a net 7-percentage point positive score on handling the economy, which will likely be the cornerstone of his re-election campaign.

Those who say they’re more likely to oppose Trump on any of these issues generally look like those who are less apt to support him in any case. Nonetheless, the differential net impacts are revealing in terms of his relative strengths and weaknesses in the eyes of the American public.

Alienation

Another poll result marks the extent of public alienation from the political and economic system: 72% of Americans say the country’s political system works mainly to benefit those in power, and 62% say the same about the economic system. Large numbers, in both cases, hold that opinion strongly.

It’s a sentiment that Trump may have harnessed to help him win the White House, but it’s working against him now that he’s in power. Trump has a 63% approval rating among those who say the political system benefits all people, and 68% approval among those who say all benefit from the economic system. But among the sizable majorities who say these systems mainly benefit the powerful, his approval ratings dive to 31% and 23%, respectively.

There’s a similar effect in terms of peoples’ willingness to consider Trump for a second term. Among those who say all people benefit from the country’s political systems, one-third say they definitely won’t vote for Trump; so do one-quarter of those who say everyone benefits from the economic system. But among those who say these systems benefit the powerful, 64% and 73%, respectively, say they definitely will not support Trump for re-election.

Vote intention

Vote intention is also revealing. Virtually as many black people as white people say they’ll definitely vote in the general election, 77% versus 80%; this falls to 60% among Hispanics, who also are less apt to be registered to vote. Among black and white voters, these numbers are 6 percentage points higher for women than men, 78% vs. 72% -- a slight but potentially important difference.

While black and women voters typically help the Democrats, this advantage varies by age. Turnout intention is substantially lower among younger adults, a more Democratic-oriented group -- 66% among 18 to 29-year-olds and 71% among those 30 to 39, versus 79% among those 40 and above. As with Hispanics, this difference is exacerbated by the fact that young adults also are less likely to register to vote in the first place; 73% of people under 40 report being registered, compared with 88% of those 40 and older.

Intention to vote rises both with education and income, which are related; voting intention is 63% among people with less than $50,000 in household income, but rises to 82% in the $50,000-$100,000 income range and 91% among $100,000 earners and above. Voting intention rises from 70% among those who haven’t graduated from college to 87% among college graduates.

Lastly, saying you’ll definitely vote on Nov. 3, 2020, is essentially equal among Democrats and Republicans, at 83% and 85%, respectively. That drops to 67% among independents, who hold the distinction of often being the key swing voter group in national elections -- yet also the hardest to engage.

Methodology

This ABC News/Washington Post poll was conducted by landline and cellular telephone from April 22 to April 25, 2019, in English and Spanish, among a random national sample of 1,001 adults. Results have a margin of sampling error of 3.5 points, including the design effect. Partisan divisions are 29-26-36%, Democrats-Republicans-independents.

The survey was produced for ABC News by Langer Research Associates of New York, with sampling and data collection by Abt Associates of Rockville, Maryland. See details on the survey’s methodology here.