After winning the Nevada Democratic caucuses, Vermont Sen. Bernie Sanders, with his wife, Jane Sanders, waves as they exit the stage at a campaign rally Saturday in San Antonio.
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Rep. Alexandria Ocasio-Cortez, D-N.Y., speaks during a rally for Democratic presidential candidate Sen. Bernie Sanders, I-Vt., in Iowa last month. She has announced a new PAC to back progressive congressional candidates.
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Democratic presidential candidate Bernie Sanders speaks during a campaign event on Monday in Richmond, Calif. The independent senator identifies as a democratic socialist.
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Harry Reid tips his hat during a November fundraiser for the Nevada Democratic Party in Las Vegas. The former Senate majority leader said Nevada's diverse population is more reflective of the Democratic electorate.
Karina Shumate, 21, a college student, filled out a voter registration form in Richardson, Texas on Jan. 18. One big registration effort this year has drawn controversy among elections officials.
Democratic presidential candidate and former Vice President Joe Biden addresses supporters Tuesday night in Columbia, S.C. Biden skipped a primary night event in New Hampshire, expecting a poor showing.
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