http://openchannel.nbcnews.com/_news/2013/03/18/17314818-cyberattack-on-florida-election-is-first-known-case-in-us-experts-say?lite
"An attempt to illegally obtain absentee ballots in Florida last year is the first known case in the U.S. of a cyberattack against an online election system, according to computer scientists and lawyers working to safeguard voting security.
The case involved more than 2,500 “phantom requests” for absentee ballots, apparently sent to the Miami-Dade County elections website using a computer program, according to a grand jury report on problems in the Aug. 14 primary election. It is not clear whether the bogus requests were an attempt to influence a specific race, test the system or simply interfere with the voting. Because of the enormous number of requests – and the fact that most were sent from a small number of computer IP addresses in Ireland, England, India and other overseas locations – software used by the county flagged them and elections workers rejected them.........
Overseas “anonymizers” -- proxy servers that make Internet activity untraceable -- kept the originating computers’ location secret and prevented law enforcement from figuring out who was responsible, according to the grand jury report, issued in December. The state attorney’s office closed the case in January without identifying a suspect.
Then came the Herald report, which said that three IP addresses in the United States had been identified among those sending the requests and that there had been a delay in getting that information to investigators, which a Miami-Dade elections official confirmed to NBC News. Terry Chavez, spokeswoman for the state attorney’s office for Miami-Dade County, also confirmed to NBC News that the investigation was reopened to look into those IP addresses. Chavez said she could release no details on the investigation........."