I have replied STOP a lot and the political texts do, in fact, stop - at least from that particular number (see my other comment for a rant about this). Of course if you do this to a scammer it is as you say.
I wonder if 'STOP or I will vote for your opponent' might work. Then again, if that worked, you might just start receiving messages asking you to vote for their opponent instead.
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.
It's so bizarre, to get political texts via SMS. Here in Europe, I have got 0 (zero) political texts in my life.
STOP to a 10DLC number should block further texts from that specific number at a carrier level, regardless of whether the campaign honors its 10DLC requirements. At least, until it’s recycled to a new campaign.