The Bush Administration may find itself relying on the kindness of a Democrat to salvage the nomination of Robert M. Gates as director of the Central Intelligence Agency. Gates's confirmation, which once seemed a sure thing, was thrown into doubt on July 9, when former CIA official Alan D. Fiers Jr. pleaded guilty to lying to Congress about the intelligence agency's role in the Iran-contra scandal. Fiers' plea has revived suspicions on the Senate Intelligence Committee that Gates, the No. 2 official at the CIA when funds were secretly diverted to the contras, knows far more about the affair than he has been willing to admit. But Intelligence Chairman David L. Boren (D-Okla.) remains a staunch supporter of Gates and could pull him through.