Hendrik Hertzberg writes for the New Yorker.

The Presidential candidacy as joke is a perennial sideshow along the raucous midway of the American political carnival. Sometimes the candidate—Will Rogers (1928), Gracie Allen (1940), Pat Paulsen (1968 through 1996), Stephen Colbert (2008)—is a fully qualified professional humorist. Sometimes he, or it, is an animal, barnyard (Pigasus, the Yippie mascot, 1968) or cartoon (Pogo, the comic-strip possum, 1952). Sometimes—like Lar Daly, the Chicago eccentric who, in 1956 and three times thereafter, campaigned in an Uncle Sam suit—he appears to be in on the joke. Sometimes he doesn’t. The first two or three times that Harold Stassen, a talented progressive who at age thirty-one had been elected governor of Minnesota, sought the Republican nomination, his candidacy was taken seriously, and rightly so. By the fifth or sixth time, he was a punch line. By the ninth—in 1992, when he was eighty-five—the poignancy of it all muted the laughter.

The joke candidate of the present moment partakes of many of the qualities of those who have gone before, but the precursor he most strikingly resembles, perhaps, is the late Bishop Homer A. Tomlinson. Like Bishop Tomlinson, the 1952, 1960, 1964, and 1968 Presidential nominee of the Theocratic Party, Donald Trump is a repeat aspirant, having previously proclaimed his readiness to occupy the nation’s highest office in 1988 and 2000. Tomlinson lived in a little frame house in Queens; Trump grew up in a big house (some two dozen rooms, twenty-foot Georgian columns on the portico) in the same borough of New York. Like Trump, Tomlinson had a business background: before joining the pastorate, he was C.E.O. of his own advertising agency. Like the Bishop, the Donald is a person of faith. Tomlinson was top man in a spinoff of the Church of God, part of the Pentecostal movement. Trump is a Christian, too. “I think that the Bible certainly is—it is the book,” Trump told an interviewer for the Christian Broadcasting Network recently. “I’m a Presbyterian. And you know, I’ve had a good relationship with the church over the years.” But the decisive similarity is a level of megalomania unusual even in people who consider themselves entitled to supreme power. Between elections, Bishop Tomlinson travelled the world with a portable throne, crowning himself, among other things, King of Belgium, King of Ethiopia, Tsar of Russia, and, finally, King of the World. Trump thinks no less highly of himself....