U.S. Sen. Robert Menendez, D-N.J., (right) speaks alongside his lawyer, Abbe Lowell, after being indicted on corruption charges in April. Kena Betancur/Getty Images hide caption

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Sen. Bob Menendez, D-N.J., speaks to reporters during a news conference in Newark on Friday. The Justice Department plans to file charges alleging that he did political favors for a friend and donor, NPR has confirmed. John Minchillo/AP hide caption

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New Jersey Democrat Robert Menendez, chairman of the Senate Foreign Relations Committee, has asked the Justice Department to investigate a smear campaign against him. Alex Wong/Getty Images hide caption

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