Former U.S. Senator Adlai Stevenson III, the namesake son and great-grandson of famous Illinois Democrat politicians, died at his Chicago home on Monday at age 90, The New York Times reports.
His wife, Nancy, said the cause of death was Lewy body dementia, according to the newspaper.
Stevenson won a special election to the U.S. Senate in 1970 after Republican Senator Everett Dirksen died in office. Stevenson, a Democrat, won re-election in 1974, but decided not to run in 1980.
He lost races for governor of Illinois in 1982 and 1986 to Republican James Thompson.
Stevenson was the great-grandson of former Vice President Adlai Stevenson and the son of former Illinois Governor Adlai Stevenson II, who lost to Republican Dwight Eisenhower in the 1952 and 1956 presidential elections.
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