So, funny story. Phone numbers are public record, especially if you included it on your voter information. If you place your name on the National Do Not Call list, the political agencies and charities are pretty much exempt from them, though each, usually, has its own internal Do Not Call list.

There's no way to get off a political polling/informational call list, because your phone number is public record and the sole goal is to get you informed about their specific goal, usually regarding a candidate or proposition.

I get it's frustrating, but it's worth hearing out at least the ones that are about local policy. I understand not caring about wider election candidates, but the others can be genuinely informative. That aside, hearing them out doesn't get them to put you on a "call me again" list either, these aren't scam callers trying to get information or repeat callbacks. For the most part they just want to get a pledge of support for a local proposition, for internal polling numbers during the campaign. Basically, "we called 5,000 people, of the 2,000 that answered, 1,000 said they would vote for Prop 38" and we all cheer.

There's also polling call centers, which get company and government contracts to conduct these polls, which again use the public information and are exempt from the National Do Not Call list.