Candidate options would appear on-screen, and the voter s selection would be recorded. The card could either be destroyed or saved depending on the requirements of the state. Absolutely, The technical problems would probably be the easiest to solve. ATMs are basically computer terminals attached to a network by telephone lines, so mechanical failures could be addressed by technicians. They would have to be compensated for reprogramming and the use of their system.
Legal problems are harder to solve.
Present election laws were enacted prior to the invention of digital technology. Some of the bugs in the system would have to be worked out in the courts. Political problems are the hardest to deal with in a society as diverse as ours. Some voters will surely feel disenfranchised.