J. Alex Halderman is a computer scientist who has shown just how easy it is to hack an election. His research group at the University of Michigan examines how attackers can target weaknesses in voting machinery, infrastructure, polling places and registration rolls, among other features. These days he spends much of his time educating lawmakers, cybersecurity experts and the public on how to better secure their elections. In the U.S., there are still serious vulnerabilities heading into the 2020 presidential contest.