Hackers switch online votes to evil sci fi robots

This year, more people than ever are voting ahead of time and online.  Click on this link to read a Washington Post article about how a group of computer scientists were able to penetrate Washington DC's online voting system and switch peoples' votes to the names of evil sci fi robots.  Fortunately, it was just an experimental test of the system, but it doesn't encourage a lot of confidence in the security of online votes.  Is cyber-space a safe place for citizens' votes to be lodged?