If you’re in Colorado you’re automatically registered. https://www.sos.state.co.us/pubs/newsRoom/pressReleases/2021/PR20210629VoterRegistration.html

It’s the only state (it was at the time of this article at least) that has true automatic registration.

Of course republicans have been trying as hard as they can to get rid of it.

https://coloradonewsline.com/2023/03/20/how-a-red-state-exodus-from-an-interstate-voter-database-could-impact-colorado-voter-rolls/