Amanda Durio, 31, is a union carpenter. She plans to caucus for Bernie Sanders because she likes his message on "race" and "social classes." Asma Khalid/NPR hide caption

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Caucuses have been plagued by embarrassing problems this election season, but they're an American tradition. Here, a ballot from Nevada precinct 3726 shows a vote for former Speaker of the House Newt Gingrich. David Becker/Getty Images hide caption

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Jan White, left, Brenda Robertson, center, and Janet Freixas, right, count paper ballots at the headquarters of the Douglas County Republican Party Saturday in Minden, Nev., following county-wide Nevada caucus meetings. Ted S. Warren/AP hide caption

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