Lincoln survived for two more years. On the books, assets ballooned to $5.46 billion, but billions were in speculative investments, and hidden losses soared. Lincoln talked many customers into replacing federally insured deposits with high-yielding bonds from Lincoln’s parent, American Continental, a Keating corporation that was drowning in losses.

Bond buyers were not told the condition of American Continental, or that its bonds were uninsured, prosecutors said. A witness in a lawsuit years later produced a Lincoln memo advising its bond salesmen to remember that “the weak, meek and ignorant are always good targets.”

American Continental went bankrupt in 1989, and an insolvent Lincoln was seized by the government. Some 23,000 customers were left holding $250 million in worthless bonds, the life savings of many, and taxpayers paid $3.4 billion to cover Lincoln’s losses. It was the largest of 1,043 S.&L. failures from 1986 to 1995. Authoritative studies show that they cost the savings and loan industry $29 billion and taxpayers $124 billion. The government sued Mr. Keating for $1.1 billion, but he said he was broke.

Convicted of fraud, racketeering and conspiracy in state and federal trials, Mr. Keating went to prison for four and a half years. Both verdicts were overturned on appeals in 1996. California dropped its case, and on the eve of a federal retrial in 1999, Mr. Keating, who always insisted he had done nothing wrong, pleaded guilty to four counts of wire and bankruptcy fraud and was sentenced to time already served.

The Keating Five — all Democrats except Mr. McCain — also insisted they had done nothing improper. The Senate Ethics Committee concluded in 1991 that none had violated laws, but it said that Senators Cranston, DeConcini and Riegle had interfered with the bank board’s inquiry and rebuked them, Mr. Cranston in the harshest terms. Senator Glenn and Senator McCain were cleared, but criticized for “poor judgment.”

Mr. Keating, a 6-foot-5-inch beanpole who walked with a swagger, never minced words about buying political influence. Asked once whether his payments to politicians had worked, he told reporters, “I want to say in the most forceful way I can: I certainly hope so.”

Charles Humphrey Keating Jr. was born in Cincinnati on Dec. 4, 1923. He attended Catholic schools and was an accomplished swimmer. He joined the Navy in World War II and became a fighter pilot but was never deployed to a combat theater. After the war, he enrolled in law school at the University of Cincinnati, won various collegiate swimming championships and was named an All-American. In 1948, he received a law degree and began practice in Cincinnati.