Alex Jane, his dad. Plausible. We don't know where he is now, he would have been mad at Jane for leaving...

I posted a theory already, but I read it over and actually thought of something better. 

One of the things that really bothered me was not knowing if Heller said or not that RJ is on that list. And if he did say that, would he lie.

Someone pointed out to me in another theory that Jane might have left fake information when they broke into his office. If I remember correctly, he put a toothpick there, and when he saw it had fallen he didn't seem to bothered, which makes me wonder. I actually really like this theory, thinking Jane is actually one step ahead of RJ and not the other way around. This might lead us to believe that RJ is not on the list, which gives me a little bit of happiness, because I do have some suspects who I like more then the ones on the list, like Mashburn. 

It doesn’t seem likely it’s him, but looking up the meaning of the name the sites I looked at said that Reede means "red", and Smith means "to strike or smite".  Interesting.

I don't exactly know who it is. I have a few theories. 

First, I've seen on a few websites and on a lot of theories on this site that Bruno Heller said that Red John is definitely on Jane's list. What I'm saying here will be using that assumption. 

First thing I have to say, I'm actually really mad that Mashburn wasn't even considered as one suspect, and Reede and the Sheriff were. I really think the RJ suspects should be one of the characters that we had a little more insight on his life or past. These two only appeared in one episode each and not only did they not seem like RJ, they weren't even one of the most important characters in that episode. Mashburn, on the other hand, even though he appeared in only a few episodes, he was really important in his episode and we got to know his pretty well. 

What I'm saying is I think RJ should be someone more memorable to the audience.

Second thing I have to say, Robert Kirkland is definitely involved in some way. He's probably not RJ, because I believe him being RJ would disappoint a lot of people, because of how obvious it would be, and that wouldn't be good for the show. A lot of people are trying to figure out how RJ knew the final names on the list before Jane. To those people I would like to remind the only other person who knew everything Jane had on the suspects, and that would be Kirkland, when he got the information after breaking into Jane's office. In my opinion, he is definitely involved with Red John, probably passing on the information to RJ, who, just as Jane, figured out the names. It's totally possible, as RJ has proved various times to be just as or smarter then Jane. 

On the other suspects:

Brett, even though he seems to be very popular and I actually think it's possible, for some reason I don't think he's RJ. RJ is assumed to be god-like, being able to get so many followers and other things, and Brett just doesn't seem that way, unless it's all an act he puts on for Jane not to really see him.

Stiles is also definitely involved with RJ. One of Stiles scenes is, in fact, one of the biggest errors  the show has committed in my opinion. When Stiles told Jane where to find Frye. Why did Jane not press on that lead, see what he knew, even though I doubt he would say something. I'm not ruling him out, but I think he doesn't have the figure or form to be RJ, unless the recent kills, none have been him. 

Bertram might be RJ, there's a lot if clues pointing to him, but I just can't picture him killing someone. 

With all of that in mind, assuming RJ is on that list, I would say RJ is Raymond Haffner. Haffner has the physical characteristics, the same ones described by Rosalind, even though I don't know if we should believe her, and he seems like what we, the audience, usually think of when we think of a villain, not a old, bald, fat guy, we think of a worthy opponent to Jane. 

All of what I just said might be wrong. Even though it's just a TV show, maybe they'll do something we have never seen before, not being like other shows, and not being afraid of anything the audience may think. I guess we'll just have to wait and find out.

I just wanted to say that I like the idea of Jane having a fake list causing RJ to reveal the real list. I honestly think PJ has been a step ahead of RJ for some time and instead of RJ toying with PJ, it's actually PJ who is toying with RJ. Thus, even though Patrick may not know who RJ is right now, he is playing around with the character of RJ thus allowing RJ to make a mistake and reveal the TRUE list! :P

The only name that Jane gave us was Bertram (during the ride with Lisbon).  He also had seen the video before he showed it to her, giving him time to match the seven pictures with the suspects that Red John gave.  And remember that he thinks that Lisbon would be unable to keep a secret, especially his "real" list.

Since he knew that someone had broken into his loft (a la, the toothpick), he must have also had a pretty good idea that that would happen.  That gave him the opportunity to display his suspects and theories in a manner that would cause Kirkland to come up with the suspect list for Red John.

I'm leaning toward Mashburn and maybe CBI Ron as an outside possibility.

First off I should note after the recent finale where Jayne revealed the seven people he had narrowed down the list to that I am assuming the writers are not going to dick us around too much and Red John is either Jayne himself, one of these seven, or a combination of these suspects.

We know Red John does not actually have psychic powers so I would like to think Jayne is finally being clever when it comes to Red John and is one step ahead of him. It would appear that the only way Red John could have predicted those seven suspects is from when Bob Kirkland had his people copy the notes from his loft.  I doubt Kirkland himself is Red John but it is obvious he is connected to Red John in some way.  I think Jayne has a plan now and knows more about who is Red John then he is letting on, leaking the info to Red John to let him feel clever and think he is still one step ahead. This would explain how he knows the seven suspects but it is still unclear about the whole "happy memory" thing but likely Jayne leaked that somehow too....

The other explanation how Red John knew the suspects and the happy memory is that Jayne is actually Red John and does not know it. Personally I really don't think this is the case but really the writers could do this if they want to be dicks...