Well, if you want to “campaign”, you'll need to do what everyone else does. Usually, that starts with founding some group and trying to attract like-minded people who agree with your principals to join. Perhaps debunk the fashionable scientific notion that humans are animals. After all, Darwinism is just a theory. Challenge the received wisdom that the very old, the mentally handicapped, and other useless eaters should be cared for.
Such sentimentalism makes bioethicists wonder if nonhuman animals of comparable sentience should be respected too.
Then you'll want to pick some specific law or regulation that you think goes too far, and launches a media campaign across multiple platforms to raise awareness, while also lobbying the politicians whose power it's within to change said law. That's hideously expensive to do, so a big part of what your group will do every day is try to fundraiser from a sympathetic public.
However, given that there isn’t actually anywhere on earth that gives animals the same legal protections as humans, and that we legally kill many tens of millions of animals a year, I’m not sure which specific laws you'd be campaigning against. I
f you can justify the action as having some tangible benefit to society (animal testing in medical research, for example), it's even legal to do things to animals that most people would describe as torture. So that leaves… what? The laws that say it's not OK to torture other living for things for no reason? The laws that say that if you choose to have a pet, you are obligated to take care of its basic needs and not intentionally harm it? Are those what you want to campaign against? If so, I suspect you'd find the well of popular support and resulting streams of funding to be awfully dry.
"Cheers"