Nothing for it but to endure the electioneering, and the charities (or "charities") are immune, but for those trying to sell a product by mail there is USPS form 1500. Yes, it says 'obscenity' but no less than the Supreme Court has said that the recipient is the sole determiner of what is considered obscene. Unfortunately you likely will have to send it yourself as clueless postmasters (at least the one here) figure that if THEY don't see it as sexual, it shouldn't be processed.