De acordo com esta discussão no quadro de mensagens do Straight Dope , é de Michael Shaara " 2066: Dia da Eleição ":
It is the year 2066. The American Government has changed dramatically. In a world where anyone can become president, there exists a system that judges the qualities of America's next leader. Its name is UNCLE SAM. Through this highly advanced supercomputer, qualified people are chosen without scrutiny and human fault. What was not foreseen, however, was SAM not choosing the next president of the United States. If something is not done, war will break out, and America will be no more. At a gathering of America's most powerful men, Harry Larkin is secretly sworn in as President. Although he is a political science professor, he manages to pull himself together in order to govern an America on the brink of a political meltdown.
Encontrei-o com termos de pesquisa eleição de presidente de contos de ficção científica especialistas diferentes realizam testes