Robert Novak Robert Novak

Robert Novak, the conservative political columnist and CNN commentator who played a key role in the Valerie Plame CIA case, has died. He was 78.

Novak succumbed to brain cancer at his Washington home on Tuesday, his wife, Geraldine, told the Chicago Sun-Times. "He was someone who loved being a journalist, loved journalism and loved his country and loved his family," Geraldine said. Novak had worked for the Sun-Times since 1966. He was diagnosed with a brain tumor last summer, less than a week after he hit a pedestrian with his Corvette. He announced his retirement days later.

Best known as the host of CNN's Crossfire, Novak's journalism career spanned half a century. Born in 1931 in Joliet, Ill., Novak started as a sports writer in his native state. He crossed over to political journalism when he became a political correspondent for the Associated Press after the Korean War.

He rose to fame in 1963 when he teamed with his lifelong writing partner Rowland Evans Jr. to write a column titled Inside Report, which gave inside scoop on Washington happenings, for The Wall Street Journal. The column was syndicated in hundreds of papers. Novak continued it after Evans retired in 1993. Evans died in 2001. The pair also edited the Evans-Novak Political Report for the Sun-Times.

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Novak and Evans joined CNN in 1980 as analysts. Soon afterward, Novak started co-hosting Crossfire

, the political debate show on which he represented the right wing. He retired in 2005 and started working at Fox News as a contributor. Novak has also appeared on numerous other talk shows, including Inside Politics and Meet the Press.In July 2003, Novak was the first to identify Valerie Plame as a CIA operative in a column that sparked a three-year federal investigation into the leak that resulted in the conviction of Bush administration official I. Lewis "Scooter" Libby for perjury. Bush never pardoned Libby, but he commuted his 30-month sentence so Libby was spared jail time. The column and its consequences took a toll on Novak, who endured criticism for it, calling it a "long and difficult episode'' in his career."I had a terrific time fulfilling all my youthful dreams and at the same time making life miserable for hypocritical, posturing politicians and, I hope, performing a service for my country," Novak wrote in his memoir, The Prince of Darkness.

Novak is survived by Geraldine, his wife of 47 years, two children and eight grandchildren.