(Bloomberg) -- Support for free trade among Americans is on the rise, as backing for President Donald Trump -- the self-described “Tariff Man” -- dips to its lowest level in more than a year, an NBC-Wall Street Journal poll released on Sunday showed.

Almost two-thirds -- 64% -- see free trade as good for the U.S., an all-time high for the survey series. Support was up 7 percentage points from the previous time the question was asked, in 2017, and up from a bare majority of 51% in December 2015. Only 27% now believe free trade is bad, citing a negative impact on key industries.

The poll was published as Washington and Beijing are locked in a battle of tariffs and counter-tariffs on each other’s products, and comes after the U.S. this month formally labeled China a currency manipulator. The trade tension has sent U.S. share markets tumbling, knocked down growth in China and raised fears that a global recession could result.

Trump’s approval rating of 43% was down 2 percentage points from July, while 55% of those surveyed said they disapprove of the president, up 3 points. The net approval rating of minus 12 percentage points was the lowest in the survey series since April 2018.

Only 40% of poll respondents said they would definitely or likely vote for Trump in 2020.

Biden, Warren

“This is not an attractive set of numbers for an incumbent,” said Republican pollster Bill McInturff, who conducted the survey with Democratic pollsters from Hart Research Associates.

The good news for Trump is that the popularity of many of his likely Democratic opponents in 2020 is also weak.

Front-runner Joe Biden plunged to a net negative rating of 4 percentage points from a net positive of 32 points in January, before the former vice president formally entered the race. Opinions of Senator Bernie Sanders and Senator Elizabeth Warren, two of the other leading Democratic hopefuls, are also net negative.

McInturff said the survey suggests the general election will feature two unpopular nominees. “A year from now, both remaining candidates will have a net-negative favorable rating,” he predicted.

The survey, taken in the wake of mass shootings in El Paso, Texas, and Dayton, Ohio, showed strong support for some gun-control measures: 89% said they favor Congress expanding background checks on firearms sales, and 62% back banning the sale of selected semi-automatic weapons.

The survey of 1,000 adults was conducted Aug. 10-14 and had an overall margin of error of plus or minus 3.1 percentage points. Among 834 registered voters the margin was plus or minus 3.4 percentage points.

To contact the reporters on this story: Ros Krasny in Washington at rkrasny1@bloomberg.net;Jordan Yadoo in Washington at jyadoo@bloomberg.net

To contact the editors responsible for this story: James Ludden at jludden@bloomberg.net, Ros Krasny, Steve Geimann

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