The Simulmatics Corporation opened for business on February 18, 1959, in an office rented by Edward L. Greenfield, the company’s thirty-one-year-old president, on an upper floor of a building at the corner of Madison Avenue and Fifty-second Street, five blocks south of I.B.M.’s glittering World Headquarters. Greenfield, an adman, political consultant, and all-around huckster, pulled people in like a “Looney Tunes” magnet. “Ed Greenfield,” he’d say, flashing a Dean Martin grin, slapping a back, offering a vodka-and-tonic, palming a business card. His new company’s offices were threadbare; his ambition could hardly have been grander. “Simulmatics,” a mashup of “simulation” and “automatic,” had much the same mystique as another nineteen-fifties neologism: “artificial intelligence.” Decades before Facebook and Google and Cambridge Analytica and every app on your phone, Simulmatics’ founders thought of it all: they had the idea that, if they could collect enough data about enough people and write enough good code, everything, one day, might be predicted—every human mind simulated and then directed by targeted messages as unerring as missiles. For its first mission, Simulmatics aimed to win the White House back for the Democratic Party.

In 1960, John F. Kennedy defeated Richard M. Nixon in a campaign that carries an air of destiny, mainly because of an iconic account by the reporter Theodore H. White. In “The Making of the President 1960,” White created the myth of Kennedy as an inevitable President—King Arthur, pulling Excalibur from the stone. But Kennedy’s bid for the nomination was a long shot, his victory in the general election was one of the closest in American history, and his campaign deployed an election simulator. However commonplace now, this was new then, and fiercely controversial. White, while never naming Simulmatics, took the trouble to disavow its influence on the very first page of his book. “It is the nature of politics that men must always act on the basis of uncertain fact,” he wrote. “Were it otherwise, then . . . politics would be an exact science in which our purposes and destiny could be left to great impersonal computers.” White was close to the Kennedy campaign, and the Kennedy campaign had decided to deny, publicly, that it had used Simulmatics.

In 1959, the Democratic Party, at war with itself, was being driven to the grave by segregationists. Republicans had held the White House since Eisenhower’s victory in 1952. Twice, Illinois’s governor, Adlai E. Stevenson, had failed to defeat him. In 1952, Stevenson had had a segregationist as his running mate, and in 1956 he told a mostly Black audience in Los Angeles that desegregation ought to “proceed gradually.” Adam Clayton Powell, Jr., an African-American congressman from New York, and a Democrat, damned his party for its cowardice, and endorsed Eisenhower. Even with a new running mate, Stevenson won only states that had been claimed by the Confederacy. Nevertheless, he enjoyed nearly universal support among white liberal intellectuals, including the historian Arthur Schlesinger, Jr., the economist John Kenneth Galbraith, the poet Archibald MacLeish, and The New Yorker’s John Hersey; all four drafted speeches for Stevenson, erudite and elegant. The Eisenhower campaign, meanwhile, ran what Stevenson supporters called a Corn Flakes Campaign: it sold its candidate like laundry detergent. “I think of a man in the voting booth who hesitates between two levers as if he were pausing between competing tubes of toothpaste in a drugstore,” one of his campaign consultants said. “I Like Ike,” the TV jingle ran. “It’s time for a change,” Eisenhower said, in meaningless ad copy written by the guy who came up with M&M’s “Melts in your mouth, not in your hand.”

Ed Greenfield, whose political-consulting firm worked on the Stevenson campaign in 1956, concluded that his speeches were too brainy. “The Emphasis upon Complexity Should Be Minimized,” the company’s social-science division recommended. But Stevenson refused either to simplify or to abandon his quisling position on civil rights. Nixon, Eisenhower’s Vice-President, was a formidable candidate, and a ferocious adversary. To beat him in 1960, Greenfield thought, Democrats needed a secret weapon.

Modern American politics began with that secret weapon. Greenfield called it Project Macroscope. He recruited the best and the brightest, many of whom had been trained in the science of psychological warfare. “The scientists are from the Massachusetts Institute of Technology, Yale, Harvard, Columbia, and Johns Hopkins,” the New York Times reported. Simulmatics’ 1960 election project was one of the largest political-science research projects ever conducted. Led by an M.I.T. political scientist named Ithiel de Sola Pool, the chairman of Simulmatics’ research board, Greenfield’s scientists compiled a set of “massive data” from election returns and public-opinion surveys going back to 1952, sorting voters into four hundred and eighty types, and issues into fifty-two clusters. Then they built what they sometimes called a voting-behavior machine, a computer simulation of the 1960 election, in which they could test scenarios on an endlessly customizable virtual population: you could ask it a question about any move a candidate might make and it would tell you how voters would respond, down to the tiniest segment of the electorate.