The Democratic presidential hopefuls are focused squarely on South Carolina ahead of its crucial primary on Saturday, even as the nominating contest is about to go national.

With his strong showing Saturday in Nevada, Sen. Bernie Sanders (I-Vt.) has built on his lead in delegates needed to win the nomination at the Democratic National Convention.

South Carolina — the site of a Tuesday night debate — will be key to gaining momentum ahead of next week for former vice president Joe Biden; former South Bend, Ind., mayor Pete Buttigieg; Sen. Elizabeth Warren (Mass.); Sen. Amy Klobuchar (Minn.); and investor Tom Steyer. Former New York mayor Mike Bloomberg did not contest Nevada and will not appear on the ballot in South Carolina. But he is making a play for Super Tuesday states.

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⋅ Bernie Sanders built a diverse coalition to win Nevada. South Carolina offers a tougher test.