That was more than a decade ago, but >Georgia still uses the AccuVote TS. The state is one of five ― the others are Delaware, Louisiana, New Jersey and South Carolina ― that rely entirely on DREs for voting. Ten other states use a combination of paper ballots and DRE machines that leave no paper trail. Many use a newer version of the AccuVote known as the TSX ― even though computer scientists have demonstrated that machine, too, is vulnerable to hacking. Others use the Sequoia AVC Advantage, which Princeton professor >Andrew Appel demonstrated could be similarly manipulated in a >2007 legal filing. Appel bought a Sequoia machine online for $82 and demonstrated that he could remove 10 screws and easily replace the Sequoia’s memory card with a modified version that would alter the outcome of an election.
Source : http://www.huffingtonpost.com/entry/electronic-voting-machines-hack-russia_us_5967e1c2e4b03389bb162c96