US Sen. Bernie Sanders speaks at a campaign rally in Chicago in March 2019. Sanders, an independent from Vermont, is the longest-serving independent in the history of Congress.
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Sanders, right, leads a sit-in organized by the Congress of Racial Equality in 1962. The demonstration was staged to oppose housing segregation at the University of Chicago. It was Chicago's first civil rights sit-in.
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Sanders takes the oath of office to become the mayor of Burlington, Vermont, in 1981. He ran as an independent and won the race by 10 votes.
Sanders, right, tosses a baseball before a minor-league game in Vermont in 1984. US Sen. Patrick Leahy, center, was also on hand.
In 1987, Sanders and a group of Vermont musicians recorded a spoken-word folk album. "We Shall Overcome" was first released as a cassette that sold about 600 copies. When Sanders entered the US presidential race in 2015, the album surged in online sales. But at a CNN town hall, Sanders said, "It's the worst album ever recorded."
Sanders reads mail at his campaign office in Burlington in 1990. He was running for the US House of Representatives after an unsuccessful bid in 1988.
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In 1990, Sanders defeated US Rep. Peter Smith in the race for Vermont's lone House seat. He won by 16 percentage points.
Sanders sits next to President Bill Clinton in 1993 before the Congressional Progressive Caucus held a meeting at the White House. Sanders co-founded the caucus in 1991 and served as its first chairman.
Barack Obama, then a US senator, endorses Sanders' Senate bid at a rally in Burlington in 2006.
Sanders takes part in a swearing-in ceremony at the US Capitol in January 2007. He won his Senate seat with 65% of the vote.
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Sanders chats with Dr. John Matthew, director of The Health Center in Plainfield, Vermont, in May 2007. Sanders was in Plainfield to celebrate a new source of federal funding for The Health Center.
Sanders speaks to reporters in 2010 about the Obama administration's push to extend Bush-era tax cuts. Three days later, Sanders held a filibuster against the reinstatement of the tax cuts. His speech, which lasted more than eight hours, was published in book form in 2011. It is called "The Speech: A Historic Filibuster on Corporate Greed and the Decline of Our Middle Class."
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Sanders and US Rep. Jeff Miller, chairman of the House Committee on Veterans' Affairs, walk to a news conference on Capitol Hill in 2014. Sanders was chairman of the Senate Committee on Veterans' Affairs.
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In March 2015, Sanders speaks in front of letters and petitions asking Congress to reject proposed cuts to Social Security and Medicare.