I used to live in Maryland, but moved to New York several years ago. However, I still receive sample ballots at my former address in Maryland (which is my parent's house), because I am still on the voter's rolls in my former county.
This year, like every other year, my mother called to say I received a sample ballot for the state of Maryland. This year, I finally decided to do something about it. I looked up the county's Board of Election's contact info on the web and emailed them that I was seeking information on being removed from their election rolls. This was their reply, in total:
"We will take care of removing your name from our register. Thank you very much for notifying us."
That's it. No challenge, no authentication. No seeking information about who I was, apart from my name in my email address.
No wonder it's so easy to steal an election in this country.