Former Florida Gov. Jeb Bush had a tough week with his changing positions on the Iraq War and trying to explain whether he would have authorized it, knowing what we know now. Ross D. Franklin/AP hide caption

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Former President Bill Clinton campaigns before the 2014 elections for former Sen. Mark Pryor, center, and Mike Ross, right, the Democratic candidate for governor. Justin Sullivan/Getty Images hide caption

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Former Secretary of State Hillary Clinton speaks at the Clinton foundation's Clinton Global Initiative conference with her husband, Bill, and daughter, Chelsea, looking on. Michael Loccisano/Getty Images hide caption

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Chelsea Clinton, vice chair of the Clinton Foundation, walks on stage Sept. 23 while moderating the panel discussion "Valuing What Matters" during the Clinton Global Initiative in New York. She gave birth to a baby girl, her first child, three days later. Mark Lennihan/AP hide caption

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Former Secretary of State Hillary Rodham Clinton and former President Clinton huddle under an umbrella during inaugural ceremonies for Virginia Gov. Terry McAuliffe in Richmond on Jan. 11. Patrick Semansky/AP hide caption

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He's back! Unabashed wonk and former president Bill Clinton detangles the health care law. Danny Johnston/Associated Press hide caption

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Former President Bill Clinton hugs House Minority Leader Nancy Pelosi of California as another Democrat, Sen. Barbara Boxer of California, looks on at Wednesday's ceremony naming the Environmental Protection Agency headquarters for him. Pablo Martinez Monsivais/AP hide caption

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In the Hall of Remembrance at the U.S. Holocaust Memorial Museum, visitors can light candles in memory of the 6 million Jews killed by the Nazis and their collaborators during World War II. Nicholas Kamm /AFP/Getty Images hide caption

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President Obama, former presidents George W. Bush, Bill Clinton, George H.W. Bush and Jimmy Carter attend the opening ceremony of the George W. Bush Presidential Center on Thursday in Dallas, Texas. The Bush library, which is located on the campus of Southern Methodist University, with more than 70 million pages of paper records, 43,000 artifacts, 200 million emails and four million photographs. Alex Wong/Getty Images hide caption

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