This is why it's (sort of?) legal to do what they're doing: paying for someone to vote a specific way is illegal for sure. And paying someone to vote is also illegal. But I believe that paying someone to REGISTER to vote is legal so long as you do not actively restrict who can participate. It's also okay to pay someone to write down a plan on HOW to vote, and to pay someone to write shit on the internet.
So yeah. It's very borderline. But I think it technically passes muster
Because voting regulations are left to the State governments, and each state government does it slightly differently, often with designs that are specifically intended to disenfranchise specific voters.
Further, because of the Electoral College, it is very important WHERE you vote. If I live in New York, I can't vote in Pennsylvania. I get lumped together with everyone in New York.
So my registration ties me to a "permanent address" that aligns with a state, their electoral college contribution, and the rules they've put in place to gather, validate, and verify the vote, all mixed with manipulation over the years to swing the vote wherever possible (see: gerrymandering)