[custom_adv]
The question of who may vote is a central issue in elections. The electorate does not generally include the entire population; for example, many countries prohibit those judged mentally incompetent from voting, and all jurisdictions require a minimum voting age. Suffrage is the right to vote gained through the democratic process. Citizens become eligible to vote after reaching the voting age, which is typically eighteen years old as of 2012 in the United States.
