 Some states allow Election Day voter registration (also known as EDR) which enables eligible citizens to register to vote or update their registration when they arrive to vote.Some states call the procedure same-day registration (SDR) because voters can register and vote during an earlier voting period before Election Day.EDR allows eligible citizens to register or update their registration at the polls or their local election office by showing valid identification to a poll worker or election official, who checks the identification, consults the registration list and, if they are not registered or the registration is out of date, registers them on the spot.