Hillary Clinton is running with all the advantages and challenges of someone who has been in the public eye for more than two decades. Andrew Burton/Getty Images hide caption

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Hillary Clinton has described herself as the most famous person you don't really know. And as she launches into her second presidential campaign, she'll be reintroducing herself to voters who largely think they have her figured out. Mel Evans/AP hide caption

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Hillary Clinton in June 1969 at the Rodham family home. She was featured in a Life magazine story called "The Class of '69." Lee Balterman/The LIFE Premium Collection/Getty Images hide caption

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Would-be presidential candidates are ditching "testing the waters" and "exploratory committees" to hold onto unlimited and undisclosed cash for longer. Mark Wilson/Getty Images hide caption

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Sen. Elizabeth Warren talked about 2016 to WBUR's Here & Now: "What I care about is that everyone who runs for president, who runs for any national office right now, talks about this core set of issues." Manuel Balce Ceneta/AP hide caption

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Hillary Clinton speaks to the media after keynoting a Women's Empowerment Event at the United Nations on Tuesday in New York City. Clinton answered questions about recent allegations of an improperly used email account during her tenure as secretary of state. Yana Paskova/Getty Images hide caption

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Former Secretary of State Hillary Clinton receives the Liberty Medal in 2013 from the National Constitution Center. Former Florida Gov. Jeb Bush was the group's honorary chairman. Both are now likely presidential candidates for their respective party's nomination. William Thomas Cain/Getty Images hide caption

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Former Secretary of State Hillary Clinton speaks to reporters Tuesday at United Nations headquarters, where she said she chose to use a personal email account for government business out of convenience. Seth Wenig/AP hide caption

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U.N. Secretary-General Ban Ki-Moon (in white-and-blue vest) joins other leaders at the 2015 International Women's Day March at Dag Hammarskjold Plaza on March 8 in New York City. Michael Stewart/WireImage/Getty Images hide caption

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U.S. Secretary of State Hillary Rodham Clinton checks her mobile phone in March 2012 after her address to the Security Council at United Nations headquarters. While she's asked the State Department to quickly release her emails from her tenure as secretary, the process likely will take months — dragging out media coverage and critical questions. Richard Drew/AP hide caption

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Former Secretary of State Hillary Clinton, seen here at a U.N. event last March, has been criticized for using a private email account to conduct official business during her four years in the Obama administration. Andrew Burton/Getty Images hide caption

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