Americans are dissatisfied with President Donald Trump as he nears his 100th day in office, with views of his effectiveness and ability to shake up Washington slipping, a new Wall Street Journal/NBC News poll finds.

More than half of Americans—some 54%—disapprove of the job Mr. Trump is doing as president, compared with 40% who approve, a 14-point gap. That is a weaker showing than in the Journal/NBC News poll in late February, when disapproval outweighed approval by 4 points.

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