ELON, N.C.—John Della Volpe, who has been polling millennials for 17 years, stood before about 150 students in a gleaming new center at Elon University this fall in search of an answer.

In his 2016 survey for Harvard University’s Institute of Politics, 42% of younger Americans said they support capitalism, and only 19% identified themselves as capitalists. While this was a new question in his survey, the low percentage of young people embracing capitalism surprised him. He had come here, in part, to better understand why.

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