In a world more to his liking, Gore Vidal might have been president, or even king. He had an aristocrat's bearing — tall, handsome and composed — and an authoritative baritone ideal for summoning an aide or courtier.

But Vidal made his living — a very good living — from challenging power, not holding it. He was wealthy and famous and committed to exposing a system often led by men he knew firsthand. During the days of Franklin Roosevelt, one of the few leaders whom Vidal admired, he might have been called a "traitor to his class." The real traitors, Vidal would respond, were the upholders of his class.

The author, playwright, politician and commentator whose vast and sharpened range of published works and public remarks were stamped by his immodest wit and unconventional wisdom, died Tuesday at age 86 in Los Angeles.

Vidal died at his home in the Hollywood Hills at about 6:45 p.m. of complications from pneumonia, his nephew Burr Steers said. Vidal had been living alone in the home and had been sick for "quite a while," Steers said.

Vidal "meant everything to me when I was learning how to write and learning how to read," Dave Eggers said at the 2009 National Book Awards ceremony, where he and Vidal received honorary citations. "His words, his intellect, his activism, his ability and willingness to always speak up and hold his government accountable, especially, has been so inspiring to me I can't articulate it."

Along with such contemporaries as Norman Mailer and Truman Capote, he was among the last generation of literary writers who were also genuine celebrities — regulars on talk shows and in gossip columns, personalities of such size and appeal that even those who hadn't read their books knew their names.

His works included hundreds of essays, the best-selling novels "Lincoln" and "Myra Breckenridge" and the Tony-nominated play "The Best Man," a melodrama about a presidential convention revived on Broadway in 2012. Vidal appeared cold and cynical on the surface, dispassionately predicting the fall of democracy, the American empire's decline or the destruction of the environment. But he bore a melancholy regard for lost worlds, for reason and the primacy of the written word, for "the ancient American sense that whatever is wrong with human society can be put right by human action."

Vidal was uncomfortable with the literary and political establishment, and the feeling was mutual. Beyond his honorary National Book Award, he won few major writing prizes, lost both times he ran for office and initially declined membership into the American Academy of Arts and Letters, joking that he already belonged to the Diners Club. (He was eventually admitted, in 1999).