Brooke Buchanan, communications director for McCain, said in a statement released on the Arizona Republican's official Web site, that the hold was lifted after receipt of a report McCain had first requested "nearly a year ago."
"This report confirms Senator McCain's longstanding concerns about the poor oversight and cost overruns in intelligence technology programs," Buchanan's statement said. "Senator McCain will continue to fight to ensure American taxpayer dollars are used efficiently and effectively to strengthen our national security."
Details of the report were not provided.
Clapper, a retired Air Force lieutenant general, received unanimous Senate Intelligence Committee approval last week for his nomination as director of national intelligence. But McCain's "hold" had threatened to keep President Obama's pick from being confirmed by the full Senate until after its August recess.
Clapper would succeed Dennis Blair, who resigned in May. The acting director, principal Deputy Director David Gompert, is to leave at the end of August.
Senate rules allow members to put "holds" on nominees or bills to signal they might filibuster a vote on the matter until their concerns are addressed.