When they head to the voting booth to choose a 2008 presidential candidate, some voters also will have to make sure they take proper identification to the polls.
In some states, voters will have to show a current, government-issued photo ID.
Other states want to impose the same requirement but are waiting on a Supreme Court ruling before moving ahead.
The court is expected to rule next year on the constitutionality of an Indiana law requiring voters to show a photo ID – such as a driver’s license – issued by a state or federal agency. If it lets the law stand, other states could adopt similar measures, election experts say.