Sure, it's done automatically when you apply for a driver's license or change your registration, by the Motor Voter Act. Registering to vote is incredibly easy

Sure, it's done automatically when you apply for a driver's license or change your registration, by the Motor Voter Act. Registering to vote is incredibly easy if you keep your state documents up-to-date. We just moved states. When we got our driver's license, we checked a box to change our voting record. We received in the next week a letter from our old county asking us if we did indeed move and if we should be removed from their voter roll, as well as a letter from our new county informing us we will be voting there from now on. But... driver's licenses or state IDs aren't the end all be all. If I keep real property in another state, I could potentially qualify for a license or state ID there as well, but that state would not be my main residence and I could not be a citizen of that state unless I actually intended to move there permanently. If I lived a more transient life, I would be able to freely choose which state I wanted to be a citizen of. Like if I spend 73 days exactly in each of five states and received mail there, then I would be able to choose which state to register in. There's no way for states to know or to control my movement without imposing arbitrary and illegal restrictions.