I have suspected Luther Wainwright since the end of his first episode on the show. All it took was this look on his face as he walked away from Lisbon, something about it sent the unintentional thought through my head: "oh my gosh, he's Red John." which sent me back to his conversation with Jane the minute before. After that, the thought would not leave me mind. Through the rest of the season my eyes were opened up to little hints here and there and I can honestly say that having his character killed off was almost physically painful because I was so sure. I would like to hold out hope that my gut instincts were correct and that Red John pulled off a clever trick to fake his death.
If I was indeed wrong, I have chosen two of the final seven to be the other possibilities. They are Ray Haffner and Brett Partridge. Brett seems to be a popular one on here so if it isn't Luther it may not be him either (the popular ones always seem to be the least likely). Unfortunately, I lost my enthusiasm for figuring out who Red John is when the show appeared to have killed off Luther because I honestly and truly felt and believed that it was him (which is why I hold out the hope that it is) but I'm going to try and at least keep my theory peddling mind at work this coming season.
I have no real foundation for my accusations of the other two. I looked at them and I felt they were the right suspects to pick. Maybe my gut was wrong about Luther but it could be right about Ray or Brett; my gut is not wrong very often (which could be the problem...the writers on the show might be a bunch of people exactly like me trying to mess up and confuse other people like them/me).
One thing I know for sure is that it is NOT Kirkland. That would be far too obvious and when he killed that guy in the hospital, he asked if he knew who he was before killing him. I distinctly remember that guy saying he knew who Red John was and he said he didn't know Kirkland. Would I be surprised if Kirkland was a friend of Red John's? Heck no. In fact I am pretty sure he is because why else would you kill a suspect who knew the killer's identity? I think he asked if he knew him simply to make sure that his connection to Red John had not been exposed to "underlings" because that could ruin him. I also have serious doubts about Stiles, don't think it's him either. Bertram...nah. I am not feeling that one. I doubt it's the sheriff and no idea about Smith but still thinking no on both.
I say it's Wainwright. I want it to be Wainwright. I will be sad to finally see my theory (which I spent months building last season) laid to rest if I am wrong (which is likely) but I think having Ray or Brett turn out to be Red John would soften the blow a bit because their not too disappointing as far as suspects go.
Side not: Interesting thing about the name Ray...it only takes one letter change to make it Roy.