President Donald Trump’s supporters tend to live in areas of the country that have been left behind by the nation’s economic recovery and were won over by his promise to bring growth and jobs back to America.

They are the ranchers of the West, the coal miners of energy-rich states, and the steelworkers of the Rust Belt. As the administration works to fulfill Mr. Trump’s campaign promises, The Wall Street Journal is following voters in six counties representing the economic underpinnings of his support.

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