“We’re not asking nor paying people to pledge or promise to vote (or not vote), or even to register to vote, all of which would be illegal,” she said. “Whether people actually use the plans they make is entirely up to them — we’ll have paid up regardless.”

Musk’s PAC is limiting its participants to registered voters. That’s the key difference.

Even the Cards Against Humanity thing is apparently very close to the borderline into illegality. Musk’s is unambiguously over it.