How many states have voter ID laws?

Nearly two dozen states have laws requiring voters to show some form of identification before they are allowed to cast their ballots. Those laws are at the heart of a dispute over whether they are needed to prevent voter fraud, as Republicans claim, or intimidate minority and elderly voters, as Democrats charge. The Advancement Project, a civil rights group, released a report Monday showing that such election laws could prevent 10 million eligible Hispanics from voting in November.