He was diagnosed with Type 2 diabetes in 1994 and served as spokesman for the American Association of Diabetes Educators.
Clark, twice divorced, had a son, Richard Augustus II, with first wife Barbara Mallery and two children, Duane and Cindy, with second wife Loretta Martin. He married Kari Wigton in 1977.
AP National Writers David Bauder and Hillel Italie contributed to this report.
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