Ben Wattenberg, an author, a PBS television commentator and a professed neoconservative who vainly urged his fellow Democrats to court the nation’s centrist voters at a time when the party was moving to the left, died Sunday in Washington. He was 81.

The cause was complications of surgery, his son, Daniel, said.

After the Democrats imploded in the late 1960s and early ’70s in internecine warfare between liberal and moderate factions over the Vietnam War, Mr. Wattenberg sought to rescue the party, in his eyes, by promoting the candidacies of moderates like Senators Henry M. Jackson and Hubert H. Humphrey.

He emphasized cultural touchstones like crime, race and welfare that were worrying many Americans as much as traditional economic concerns in urging Democrats to appeal to the “middle-aged, middle-class, middle-minded, unyoung, unpoor, unblack,” who, he said, constituted the moderate majority.

It was a prescription embraced instead by a generation of law-and-order Republicans, including Richard M. Nixon in his appeals to a “silent majority.”