President Obama boards Air Force One after attending a Democratic fundraiser in Newport, R.I. in August. Ahead of this fall's midterm elections, he's not doing big public rallies for Democratic candidates, instead opting for private events. Charles Krupa/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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Cuban Premier Fidel Castro addressed the United Nations General Assembly in September 1960 in New York. A new book details secret negotiations between the U.S. and Cuba dating back to President Kennedy's administration. AP hide caption

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Republican congressional candidate Elise Stefanik, 30, says her generation "can't just complain about the problems — we have to help solve them as well, because we're ultimately inheriting them." Mike Groll/AP hide caption

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Terri Lynn Land walks in the Labor Day Parade in Romeo, Mich., on Sept. 1. Land has made some public appearances like this one but overall is running a low-key race in the state. Paul Sancya/AP hide caption

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Then-incumbent Rep. Frank Guinta, R-N.H., and then-Democratic challenger Carol Shea-Porter debate during a Sept. 2012 forum at St. Anselm College in Manchester, N.H. Guinta, who lost to Shea-Porter in 2012, is running for his old seat in 2014. David Lane/AP hide caption

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U.S. Attorney General Eric Holder, shown speaking at the Congressional Black Caucus legislative conference on Friday, will be stepping down from his position as soon as a replacement is appointed. T.J. Kirkpatrick/Getty Images hide caption

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