In MS, I think all you need it 200 people to sign up for a plate and they will make it upon review. They even sell LSU and Bama plates here. It adds $50 to you fee.
Similar here in Virginia too except the number is 350 but still I was surprised that the number of people needed to commit to them was so low. VA is apparently coo coo for specialty plates (see links below). There are tons of Parrothead (Jimmy Buffett fans) plates up here?! They also have Redskins plates.