You'll just end up on another list for the next election cycle. It's marketers - no one is forcing them to respect STOP replies, and a STOP reply is just another data point.
There is in fact quite a bit of FCC regulation around texts; see e.g. https://docs.fcc.gov/public/attachments/FCC-24-24A1.txt
Not even the next cycle, as far as I can tell if you say stop or unsubscribe, the political spam mailing list system adds a new candidate to the ~8-10 candidates they keep you loaded with