Republican Donald Trump showed signs that he is trying to get his campaign back on track amid a series of recent missteps, as a new Wall Street Journal/NBC News poll found Democrat Hillary Clinton opening a 9-point lead nationally over the New York businessman.

Mrs. Clinton’s lead, at 47% to 38%, grew from 5 percentage points before the conventions in July. The finding comes as Mr. Trump and anxious Republicans are trying to shift focus away from GOP infighting and personality politics.

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