A data contractor working on behalf of the Republican National Committee earlier this month allowed the personal data of 198 million voters to be exposed online, marking the largest ever leak of voter data in history, according to the cybersecurity firm that discovered the incident. Deep Root Analytics left 1.1 terabytes of sensitive information -- including names, home addresses, dates of birth, phone numbers and voter registration information -- on a publicly accessible Amazon Web Server, according to UpGuard.