The cause was cancer, her cousin Melissa Boyen said.
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Cornelia Ellis Snively, a dark-haired beauty known as C’nelia, married George Wallace on Jan. 4, 1971, just days before he began his second term as governor. It was the second marriage for both.

Mr. Wallace’s first wife, Lurleen Wallace, succeeded him in 1967 after his first term, when he could not run for a second consecutive term; she died in office the next year.

Cornelia Wallace was the niece of a two-term governor, James E. Folsom, known as Big Jim. The marriage was surprising to some because Mr. Wallace defeated Mr. Folsom in the 1962 race for governor and their relationship had become strained.
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Mrs. Wallace was a socially active first lady known for her lively personality. But for many, the most lasting memory of her was formed on May 15, 1972.

She was accompanying her husband on the Democratic campaign trail for president when Arthur Bremer shot him four times at a rally in Laurel, Md. A news camera captured her throwing herself over her husband’s body to shield him as he lay bleeding in a shopping center parking lot. Mr. Wallace had a long recovery from the wounds, which left his legs paralyzed.

The Wallaces divorced in 1978, amid claims that she had bugged his phone in the Governor’s Mansion. A subsequent marriage of his also ended in divorce; he died in 1998.

Mrs. Wallace entered the Democratic primary for governor in 1978, but she never campaigned hard and finished last among the 13 candidates. She later moved to central Florida to be near her sons from her previous marriage.

In 1997, Turner Network Television made “George Wallace” and cast Angelina Jolie to portray Mrs. Wallace, who criticized the script as portraying her as a shallow sex kitten.