Can you post a picture of your coop? It might be easier to see where you think the raccoon is getting in or to spot any weak-looking areas.
If it is digging to get in, I would bury wire fencing into the ground or bend it into an L-shape so it is flat on the ground and then bends up. That's how we have our run set up (with the L-shaped fencing), and we've had foxes, skunks, coyotes, dogs, etc. around our yard and no casualties so far. You can try using coyote pee around your coop like this:
http://www.mypetchicken.com/catalog...e-Repels-Rats-Raccoons-Skunks-More-p1356.aspx
I have never had to use it so I can't personally speak to its effectiveness, but I have heard it keeps predators at bay. They also have pee pellets to sprinkle over your lawn if you don't want actual coyote pee in your yard. We have had problems with groundhogs in the past, so we've set up traps, but we've only ever caught groundhogs and skunks (but we have plenty of raccoons in the area), so maybe raccoons are just harder to catch? Also, if I were a raccoon, I'm not sure I'd go for the dead chicken rather than a fresh live one in the same area. Other baits I have heard of are fish, vegetables, watermelon, cooked meat, bacon, and marshmallows if you want to try any of those. You can also try those LED lights made to look like a predator's eyes in the dark or one of those devices that makes a noise that's too high-pitched for humans to hear, but it keeps pests away. I haven't had much luck with the high-pitched noises with groundhogs, but it may work for raccoons.
That's all the suggestions I can think of without seeing your coop. Hope this helps! So sorry about your chickens; I would be devastated!
