(US) Election nightmare scenarios

US law professor Richard Hasen considers five election nightmare scenarios in Slate:

Nightmare Scenario No. 1: Litigation Following Voting Glitch
The one lesson you would have thought everyone learned from Florida 2000 is that we need to use reliable equipment to cast ballots. After all, it was Florida's antiquated punch-card voting system—along with legal wrangling over whether and how punch-card votes should be counted—that led to the Supreme Court's decision in Bush v. Gore ending the Florida recounts and handing that election to George W. Bush.

After the election, the well-respected Caltech-MIT Voting Study found that 1.5 million votes were lost because of punch cards, and there were many other problems caused by both machinery failures and poor ballot design...