We have
Bike Walk Mississippi. I don't know anything other than what on their website and I do have their Affinity license plate on my vehicle which I understand gives them a portion of my tag fee to support them.
I see many similar organizations in other states. Don't know if there is some larger organization they are affiliated with. I'm sure they'd be happy to hear from you. Whether they can help you I don't know.
They do occasionally get mentioned in news and media.