Raccoons are smart, they learn from the obstacles you put in front of them. They're persistent, so they'll keep coming back until they realize there is nothing to come back to. Staples and chicken wire won't hold them, they will use their nails to pick at the staples and bend the wire until they can get inside. And they love chicken, they'll even reach their hand in and pop the chickens' heads right off - not sure if it's for fun or what.
I have a game camera outside my perimeter fence, and I've seen them coming around that fence 2-3 times a night, looking for weak spots. Once they get through that fence, they smell my dogs, so I've kept them from getting too close to the coop. Once they're at the outside run of the coop, they'd have to break through the chicken wire (without my dogs hearing it), then they face the actual coop with 1/4" hardware cloth screwed to a metal frame. I've trapped probably 2 dozen in the past year and killed 3 in the past few weeks that were brazen enough to try to climb my perimeter fence at dusk while I was outside.
I've heard a lot of good things about electric fences, I just haven't tried it myself, yet.