Keating had been living in Phoenix, where he made a fortune in real estate before buying Lincoln Savings & Loan, an Irvine, Calif., company, in 1984.
He died late Monday, his family said.
Keating's involvement in the savings and loan business at a time when banks were taking advantage of deregulation made him very rich. It also sent him to prison.
Lincoln's assets quadrupled in three years to $3.9 billion. But federal regulators eventually said that depositors' money was being gambled on risky loans.
Keating, who had already served on a federal pornography commission under President Richard Nixon, enlisted high-profile help. Alan Greenspan, the future Federal Reserve chairman, wrote a report that said Lincoln, a subsidiary of Keating's real estate company, American Continental, was sound and had "seasoned and expert" managers.
Senators Alan Cranston, D-Calif., Donald W. Riegle Jr., D-Mich., John Glenn, D-Ohio, Dennis DeConcini, D-Ariz. and John McCain, R-Ariz., became known as the "Keating Five." Keating gave them large campaign contributions, and they worked on his behalf with regulators.
After being convicted of fraud and racketeering, Keating spent more than four years in prison. He entered a guilty plea after his convictions were overturned in 1996 and was sentenced to time served.
[New York Times]