Chickens are not jungle fowl. They've been domesticated for centuries and have been bred for specific traits that don't necessarily help with the qualities they need to survive in the wild.
Jungle fowl are smaller birds, so don't need as much food, the hens lay few eggs so don't need as much protein or other nutrients, and these birds move on when they've exhausted their food supply. Also, they come from a tropical climate where it stays warm all year and food is more likely to always be available. They are also wary and flighty, and much, much better at avoiding predators.
So to answer your question, I don't think that chickens can survive long term as free range birds on one property. They need a continual supply of good food and they are just not built to last in the wild. Even semi-wild chickens in places like Hawaii and Florida take hand outs whenever they can, and those that survive are usually some type of game fowl that are closer to their wild ancestors than most chickens.
