Phone calls
At least in the United States, we call a specific place and have our phone numbers placed on a do-not-call list, charities, politicians, and businesses we have used are exempt from the do-not-call order. If someone does call, they sometimes use random dialing, I ask how this number was found, and say"remove it from the list", and hang up. Last few weeks when it was time for a meal, always there were several calls urging us to attend the caucuses, or urging us to vote for a particular candidate--but that ended until the election in November.