The absolute worst offenders are political campaigns, PACs, parties, and candidates. I believe because they're exempted from robocall and spam legislation so feel they have carte blanche. I've donated to local candidates from several different parties, and subsequently my addresses ended up in lists with national organizations and their associated PACs. I get what I would call "extremist" content endorsed and sent by both major parties in the US (DNC and RNC) about their opposition, often on the same day about the same issue, although begging for money.

The worst part though is they also SPIM me, I predominantly get text message spam from these campaigns. The Democratic party is the worst here. I volunteered to man the phones one year for a candidate during the primaries, and now they are CONSTANTLY texting me to try to get money or otherwise support candidates on the national stage, most of whom I despise. The Republicans send me postal mail and email, but no text messages or IMs.