Wisconsin Gov. Scott Walker dropped out of the presidential race on Monday, September 21. He was seeking the Republican Party's nomination.
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Walker fields questions from Bruce Rastetter at the Iowa Agriculture Summit on March 7, 2015 in Des Moines, Iowa.
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Walker speaks at the annual Conservative Political Action Conference at National Harbor, Maryland, outside Washington, D.C. on February 26, 2015.
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Walker speaks to guests at the Iowa Freedom Summit on January 24, 2015, in Des Moines, Iowa.
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Walker speaks at his election night party November 4, 2014, in West Allis, Wisconsin. Walker defeated the Democratic challenger Mary Burke.
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Walker shakes hands with Democrat challenger Mary Burke before facing off in a debate at the WMVS-TV studios October, 17, 2014, in Milwaukee, Wisconsin.
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Walker has a scarf put on his head during a special service at the Sikh Religious Society of Wisconsin for the victims of the shooting at the Sikh Temple of Wisconsin the previous day, on August 6, 2012, in Brookfield, Wisconsin.
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Walker speaks during the Republican Jewish Coalition spring leadership meeting at The Venetian Las Vegas on March 29, 2014.
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Scott Walker (left) shakes hands with Chinese President Xi Jinping (center) before a meeting as Iowa Governor Terry Branstad (right) looks on at the Great Hall of the People in Beijing on April 15, 2013.
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Walker poses with a woman during the Republican National Convention at the Tampa Bay Times Forum on August 28, 2012, in Tampa, Florida.
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Walker prepares to cast his ballot at Jefferson School to vote in the gubernatorial recall election June 5, 2012, in Wauwatosa, Wisconsin.
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Walker (right) listens to Louisiana Gov. Bobby Jindal speak as they campaign at the Waukesha Victory Center on May 24, 2012, in Waukesha, Wisconsin.
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Walker addresses the National Rifle Association Leadership Forum April 13, 2012, in St. Louis, Missouri.
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Walker stands on the North Lawn of the White House before making remarks to the news media after a meeting of the National Governors Association with President Barack Obama on February 27, 2012.
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President Barack Obama receives a Milwaukee Brewers baseball jersey from Walker (left) as he disembarks from Air Force One upon arrival at General Mitchell International Airport in Milwaukee, Wisconsin, February 15, 2012.
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Walker listens during the 2011 Governors Summit of U.S. Chamber of Commerce June 20, 2011, in Washington, D.C.
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Members of Code Pink (left to right) Medea Benjamin, Liz Hourican and Tighe Barry, hold signs to protest as Walker (center) takes his seat during a hearing before the House Oversight and Government Reform Committee April 14, 2011, on Capitol Hill in Washington, D.C.
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Walker holds a letter from democratic State Sen. Mark Miller, one of the fourteen Wisconsin state senators who fled the state over two weeks ago, during a press conference on March 7, 2011, in Madison, Wisconsin.
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Walker holds up a 'Wisconsin is open for business' bumper sticker as he speaks during a ceremonial bill signing outside his office at the Wisconsin State Capitol on March 11, 2011, in Madison, Wisconsin.
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Walker delivers his budget address to a joint session of the legislature at the capitol March 1, 2011 in Madison, Wisconsin.
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Walker speaks at a news conference inside the Wisconsin State Capitol February 21, 2011, in Madison, Wisconsin.
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President Obama receives a Green Bay Packers NFL football team jersey with 'Obama #1' written on it from Walker (left) at Austin Straubel International Airport in Green Bay, Wisconsin, on January 26, 2011.