President Obama talks with Malaysian Prime Minister Najib Razak at the East Asia Summit in Myanmar in November. Obama is trying to strike a 12-country Trans-Pacific Partnership, which would include Malaysia. Christophe Archambault/AFP/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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Sen. Elizabeth Warren, of Massachusetts, speaks to a group of supporters at a rally in support of Kentucky Democratic candidate Alison Lundergan Grimes in June. Timothy D. Easley/AP hide caption

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"Who does Washington work for?" asked Sen. Elizabeth Warren, D-Mass., after her bill that would let people refinance student debt was shot down in June. It was a question she came back to repeatedly in an NPR interview on the Goldman Sachs bailout and federal regulation of the financial sector. J. Scott Applewhite/AP hide caption

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Sen. Elizabeth Warren, D-Mass., at a November hearing of the Senate Banking, Housing and Urban Affairs Committee. A recent op-ed critical of Warren's brand of economic populism sparked an intraparty dispute among Democrats. Jacquelyn Martin/AP hide caption

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Sen. Scott Brown, R-Mass., attends the Republican National Convention in Tampa, Fla., on Aug. 30. Scott lost his re-election bid, but could be running for office again in a matter of weeks. Chip Somodevilla/Getty Images hide caption

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Republican U.S. Sen. Scott Brown (left) answers a question during a debate against Democratic challenger Elizabeth Warren on Monday at the University of Massachusetts in Lowell, Mass. Matt Stone/AP hide caption

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Bill Connell of Weymouth, Mass., who supports Republican Sen. Scott Brown, stands near signs supporting Brown's Democratic challenger, Elizabeth Warren, before the candidates' first debate Thursday in Boston. Michael Dwyer/AP hide caption

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Massachusetts Senate candidate Elizabeth Warren is shown here attending a 2010 Capitol Hill hearing on the Troubled Asset Relief Program. Alex Wong/Getty Images hide caption

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