here is the spec of the poll NIP. https://github.com/nostr-protocol/nips/pull/1346

A brief idea.

A person is appointed as head of the vote.

When you call someone to vote you take the electoral list, so maybe you can take any list and say I accept only these votes from these npub, and after the duration of the vote, so you need a time of expiration of the vote. And then you show the results