U.S. Sen. Rand Paul delivers remarks while announcing his candidacy for the Republican presidential nomination during an event in Louisville, Kentucky, on Tuesday, April 7.
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Paul and his wife, Kelley, wave to supporters in Louisville on April 7.
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Paul speaks in Rochester, New Hampshire, prior to meeting potential voters in March.
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Paul walks on stage before speaking at the Values Voter Summit in Washington in September.
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Paul attends a Senate Foreign Relations Committee hearing on Syria in September.
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Paul speaks at a news conference in June about the U.S. role in Syria.
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Speaking at the University of California at Berkeley in March 2014, Paul speaks on the issues of privacy and curtailing domestic surveillance.
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Paul addresses the 2014 Conservative Political Action Conference, where he easily won the presidential straw poll.
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From left, U.S. Sens. Cory Booker, Kirsten Gillibrand and Paul attend a March 2014 news conference to announce a new medical marijuana bill at the U.S. Capitol in Washington.
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In February 2014, Paul announced that he was suing President Barack Obama and top national security officials over the government's electronic surveillance program made public by intelligence leaker Edward Snowden.
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Paul leaves the Capitol in March 2013 after staging a filibuster over the nomination of CIA Director John Brennan.
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Ethics laws prevent senators from accepting payment for any job other that their duties in Washington. So Paul, a veteran eye surgeon, performs pro-bono procedures to keep current on his practice.
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Paul speaks in Bowie, Maryland, in March 2013 during a discussion on reforming the criminal justice system.
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Paul and his father speak with supporters in Ames, Iowa, before the start of a 2012 presidential campaign event.
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Paul boards an elevator after attending a Republican caucus meeting in Washington in July 2011.
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Paul unveils his own version of the federal budget during a news conference in March 2011.
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Paul speaks to hometown supporters in Bowling Green, Kentucky, during his campaign for the Senate in November 2010.
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Paul and his family celebrate his 2010 Senate victory during an election night party in Bowling Green.
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Coming from his son's soccer game, Paul wears shorts and a suit jacket while preparing for his guest spot on a Fox News television program in May 2010.
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Paul waits to tour a mine in Pineville, Kentucky, in May 2010.