WASHINGTON — Political columnist Robert Novak, a diehard conservative, pugilistic debater and proud owner of the "Prince of Darkness" moniker, has died after a battle with brain cancer.

His wife of 47 years, Geraldine Novak, told The Associated Press that he died at his home in Washington, D.C. early today. He was 78.

A household face as co-host of CNN's "Crossfire," Novak had been a columnist for the Chicago Sun-Times for decades. He was diagnosed with a brain tumor in July 2008, less than a week after he struck a pedestrian in downtown Washington with his Corvette and drove away.

"He was a Washington institution who could turn an idea into the most discussed story around kitchen tables, congressional offices, the White House, and everywhere in between," Senate Republican Leader Mitch McConnell of Kentucky said in a statement.

In recent years, Novak ended up actually being a part of a big Washington story, in ways he likely never intended, becoming a central figure in the Valerie Plame CIA leak case.

Novak was the first to publish the name of CIA employee, and he came under withering criticism and abuse from many for that column.

Novak, editor of the Evans-Novak Political Report, had been a columnist for the Chicago Sun-Times for decades. He is perhaps best known as a co-host of several of CNN's political talk shows, where he often jousted with liberal guests from 1980 to 2005. One of the best-known was "Crossfire."