What are currently legal limitations to the right to vote?

In order to vote in the United States or any of its states, a person must be a citizen of the United States and a legal resident of the particular state or political subdivision, must be at least 18 years of age, and must not be disqualified from voting (for example, because he or she is a convicted felon). Particular states have their own laws regarding registration to vote, some of which require registration prior to election day, others of which allow registration at the time of voting. To register, the person must usually present some kind of proof as to his or her residence.