The scammers always have a field day with elections because so many people are too politically charged to do research. By LAW, every US campaign has to have the actual name of the person who's sending texts and if it doesn't, you know it's a scam. If you have T-Mobile, you can forward the text to 7726 (SPAM) and they'll shut it down. Never ever respond to these. Don't even say "STOP" because then they'll know it's a number connected to a real human and not a business... a human they can scam.

US politicians not making literally everything about race challenge [IMPOSSIBLE]

In regards to not having signed up, depending on what state you're in, the parties can query your voter records, some states make your phone number available in those queries. There are other avenues too, like Colorado's DMV sells your personal information to third parties without your consent, for example.

Meanwhile I've actually donated and gotten zip,

Someone probably gave them your phone number

Look, no campaign wants to annoy voters but also they want everyone to be contacted. Just respond with "STOP" and it will stop. Unfortunately, every campaign buys your data so nearly ever campaign will send you a text.

Also, they use various services to send these texts so each the numbers sent from will change so you can't just block them.

This is what dying of cringe in text message format looks like.

I have definitely seen an uptick in these over the last two weeks. Multiple times a day, some calls, too. I was involved in some activism 10-15 years ago so I accept it (still baloney tho). It has started on my work phone as well...

That looks like a desktop app. You can send SMS from your non mobile computer?

I would be afraid its a trap, like clicking the link might add me to a radical MAGA hit-list or something.

Your instinct is wrong. If you want them to stop, you have to tell them to stop.

Yes, they will add you to other phone lists, but I think they'll do that whether you text STOP or not. Also, it takes like 5 seconds.