The classified Foreign Intelligence Surveillance Act program was on the brink of expiring by year's end. The 73-23 vote sent the bill to a supportive President Barack Obama, whose signature would keep the warrantless intercept program in operation for another five years.
The Senate majority rejected arguments from an unusual combination of Democratic liberals and ideological Republican conservatives, who sought to amend the bill to require the government to reveal statistics showing whether any Americans were swept up in the foreign intercepts. The attempt lost, with 52 votes against and 43 in favor.
The Obama administration's intelligence community and leaders of the Senate's intelligence committee said the information should be classified and opposed the disclosure, repeating that it is illegal to target Americans without an order from a special U.S. surveillance court.
The group seeking more disclosures also sought -- unsuccessfully -- a determination by the government of whether any intelligence agency attempted to use information gained from foreigners to search for information on Americans without a warrant, referred to as "back-door" searches. The prohibition against targeting Americans without a warrant protects Americans wherever they are, in the United States or somewhere else.
Dean Boyd, a Justice Department spokesman, said after the bill was approved that communications collected under the program "have provided the intelligence community insight into terrorist networks and plans" and have "directly and significantly contributed to successful operations to impede the proliferation of weapons of mass destruction and related technologies."
Boyd said intercepted communications also revealed potential cyber threats against the United States, including specific potential computer network attacks.