A native New Yorker whose swashbuckling career as a wildcatter in the oil fields of Texas and Louisiana paralleled and often intersected with that of President George H. W. Bush, whom he served as a fund-raiser, confidant, political adviser and secretary of commerce from 1989 to 1992, died at a Houston hospital. He was 82 and lived in Houston.
Mr. Mosbacher was the son of a Wall Street runner who later made a fortune as a specialist and trader on the Curb Exchange, the predecessor of the American Stock Exchange. As a teenager, he shuttled between the Choate School in Connecticut and the family’s 43-acre estate in White Plains, where visitors included George Gershwin (who wrote “Summertime” there) and Ethel Merman.
After graduating from Washington and Lee University in 1947 and working for a year with his father, who had oil investments in Texas, Mr. Mosbacher struck out on his own with the help of a parental grubstake of about $500,000.
With business success came an increasing role in politics, first by raising money for two failed Bush campaigns for the United States Senate that bracketed a successful one in 1966 for the House. In the 1970s, he served as finance chairman for President Gerald R. Ford. In 1988, he presided over a fund-raising effort that yielded an estimated $75 million and helped propel Mr. Bush into the White House.
Mr. Mosbacher married his first wife, the former Jane Pennybacker, by eloping when he was 19; he didn’t tell his family for six months. He adopted her religion, saying in his memoir, “My religion is Presbyterian, my heritage is Jewish — and I am proud of that.” She died in 1970.
They had three daughters — Diane, known as Dee, Kathryn and Lisa — and a son, Robert Jr., who succeeded his father as head of Mosbacher Energy and who led the Overseas Private Investment Corporation, a federal agency, in the administration of George W. Bush. The children survive him, as do six grandchildren and one step-grandchild.
Mr. Mosbacher is also survived by his fourth wife, Michele McCutchen, a Houston writer known as Mica whom he married in 2000.
His marriage to Sandra Smith Gerry ended in divorce in 1982. In 1984 he married Georgette Paulsin, herself twice previously married, who three years later paid $31 million for a Swiss maker of high-end beauty products called La Prairie.
They divorced in 1998; after she wrote about their relationship in a book, “It Takes Money, Honey,” Mr. Mosbacher said the split had resulted mainly from disagreement over where to live, he wishing to spend most of his time in Houston, she in New York City.