Is it a mistake to go to the “unsubscribe” link on their emails? That is what I do, and it seems to work.
Well, it kinda works. They might take you off THEIR list but no reason they won’t pass you on to the party or someone else’s list.
Might be more of a problem if a candidate is endorsed by the GOP-E, as in this case.
Mistake because you just confirmed it is an active email account and can be sold to spammers.
Ethical sites will honor your unsubscribe request and just remove your email address from their lists. Unethical ones will consider that request a confirmation they’re reaching a live address and sell that address to other unethical companies.