…on, poll workers copy the ballot design from a regular desktop computer in a government office, and use removable media (like the memory card from a digital camera) to load the ballot onto each machine. That initial computer is almost certainly not well secured, and if an attacker infects it, vote-stealing malware can hitch a ride to every voting machine in the area. There’s no question that this is possible for technically sophisticated attackers. (If my Ph.D. students and I were criminals, I’m sure we could pull it off.) If anyone reasonably skilled is sufficiently motivated and willing to face the risk of getting caught, it’s happened already.