Brazil’s rapid election count puts spotlight on voting security ahead of US midterms

SAO PAULO, Brazil— About 125 million Brazilians voted Oct. 4 on machines that print no paper ballots. Less than four hours after polls closed, the country knew its presidential election was headed to a runoff between conservative challenger Flavio Bolsonaro and leftist President Luiz Inacio Lula da Silva.

That process has been in place for over three decades, and Brazilians have become accustomed to its speed, simplicity, accuracy and routine. The system is robustly audited, completely disconnected from the Internet...