Note: Almost EVERY state that allows online voter registration requires a driver’s license or state ID number from the SAME state in which you are registering to use their online registration tool. This includes Illinois, which allows online registration, but only for registrants who have an Illinois driver’s license or state ID. Northwestern students who want to register at their campus address but do NOT have an Illinois driver’s license or state ID must use the mail-in registration form. For this, and for any state that requires additional steps, NU Votes can help.
District of Columbia
Source: National Conference of State Legislatures