A woman signs a giant banner printed with the preamble to the U.S. Constitution during a demonstration against the Citizens United ruling in Washington in October 2010. Chip Somodevilla/Getty Images hide caption

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Sen. Jeanne Shaheen (D-N.H.) in the U.S. Capitol building May 14, 2013. Groups are creating ads in New Hampshire to attack Shaheen 10 months before the midterm congressional elections. Allison Shelley/Getty Images hide caption

itoggle caption Allison Shelley/Getty Images