If you're one of 21 million eligible voters who don't possess a government-issued photo ID, there's a good chance you won't be able to cast a ballot this year. By October, 30 states had enacted voter-ID laws in some form, with legislators claiming that the measures prevent voter fraud (a largely non-existent issue).
Others decried the ID laws as tantamount to the poll taxes of the Jim Crow era, citing the populations affected: mostly young and uneducated minorities. Try to navigate around the requirement by filling out a state-issued provisional ballot, and if possible, filling out an affidavit for exemption. If you don't have identification on election day but may in the near future, fill out the provisional ballot and provide ID within the allotted time frame.