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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Indiana Senate President Pro Tem David Long (left) and House Speaker Brian C. Bosma, both Republicans, discuss their plans for clarifying the Indiana Religious Freedom Restoration Act during a news conference today at the Statehouse in Indianapolis. Michael Conroy/AP hide caption

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Sen. Christopher Dodd, D-Conn., left, with then-Senate Minority Leader Tom Daschle at a 1995 news conference on Capitol Hill. Harry Reid took over as leader in 2005 after Daschle unexpectedly lost his re-election. At the time, Reid was unknown to most Americans, but he beat back a challenge Dodd. John Duricka/AP hide caption

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Sen. Charles Schumer of New York stands a podium March 3 as Senate Minority Leader Harry Reid of Nevada looks on. Reid is backing Schumer to be his replacement as Democratic leader. J. Scott Applewhite/AP hide caption

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Senate Minority Leader Harry Reid of Nevada and Sen. Charles Schumer, D-N.Y. Reid said today that he won't seek re-election in 2016, adding he wants Schumer to succed him as the Democratic leader in the Senate. Molly Riley/AP hide caption

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