Assuming that Red John is even part of the original seven, then Ray Haffner.

Red John is all about power. Pretty unilaterally.

Gale Bertram is out. Ingrained character flaws/age/existing position of power/ineptitude/general lack of suave. - not it, can't be, would be a stretch, and a disappointment.

Thomas McAllister is a sheriff in wine country. I  see no indication, given any of his forays on screen, that he would be red john. He is not weak/he has a position as a defender/he has no need want for further power/he has a sense of order, justice/he never seems manipulative or controlling (dominant traits, difficult to hide characteristics)/old. -nope

Bret Stiles is laughable. He is the lead of a cult/religion/political dynamo. Excess of power. Manipulative but not in the same way as red john. Red john is fairly petty. Stiles is not. People believe in him. He is a predator for sure, no question. He actually has great chemistry with Jane. He has true conviction, believes in himself, confident. He is old, really old. I doubt his ability to carry out these types of murders unassisted. Stiles is proud but not proud enough to refuse help. Red John would never get help, he would manipulate people to serve him. Stiles seeks help/aid/guidance on various occasions. -Least likely to be Red John. (But Red John is definitely a member of Visualize)

Reede Smith well he is Reede Smith. Emotional and Power assertive. He controls his environment. He belittles and bullies people who become obstacles. He lacks sideways/logical/coherent/decisive thinking. He doesn't have the stature/influence/position/drive/will/personality/speech patterns to be red john. -not it, at most a pawn.

(Spoiler if you haven't started season 6)


Brett Partridge. Have to admit, I liked him for RJ because of his voice. He is at most a pawn. Pawns just love to kill themselves to further the plot. He is a CSI agent, in the best position to inform RJ about copycats. He doesn't really look or seem like he needs power. Working with the dead may depict a fixation with death, subsequently power control. He would be in a position of weakness, striving for power. (Most likely position for RJ). All this assuming he is even alive (probably not). I believe Partridge was connected to Visualize, providing ample opportunity for his mind to be twisted by a stronger willed individual. -most likely dead, though liked his voice

Bob Kirkland a shadowy intergovernmental agent. Yeah not seeing it. Little screen time. Motive? He doesn't seem at a lack for power. He certainly enforces his power and influence. These jobs (government jobs) are crazy time consuming. Who would have the chance to kill someone between shifts looking for other murderers? I don't see it at all. To many big dots would have to put on the board to consider this one. - likely not it, at most a pawn, at least for now.....

Ray Haffner. Gotta love this guy for RJ. I mean come on he has everything going for him. Age/stature/demeanor/personality/vibe/eyes/speech patterns/position of power/fixation/suave nature/untouchable air/history with Visualize/relationship with lisbon/knowledge of CBI/controlled the case/knowledge of intergovernmental relations/involvement with task-forces. He is in the worst (most unrestricted and far reaching) type of power. Unregulated/sideways/direct/protected by technicality/smoke and mirrors/connected. Oozes misuse and abuse. He is the ONLY one I believe could charm not One but Multiple women to do his bidding. He comes off as that kind of guy. Hell most of the people he kills have been women. These women are almost certainly a proxy for something (Lisbon?)(He hasn't been able to touch her)(He is obviously interested). Tired of listing, it goes on for another paragraph. If anything, he has a stacked deck against him, too perfect. - of the seven, he is the one, no doubt. (can someone say fall guy?)

OR

None of them are Red John. Personally, I don't think any of them are truly capable. I am anticipating a much more lucrative plot twist. Have fun everyone. Muse away.

i will just post those two pictures :

RJ at S02E023 :

http://i.imgflip.com/4a7bq.gif

Ray Haffner S06E02 :

http://i.imgflip.com/4a7e2.gif

:)

Theory on the Fake List:
So we know that Brett Partridge has already been killed...
Next episode, there will be a murder at the Visualize Headquarters...
In the preview for the next episode, the dead man on the ground looks like it may be Jason Cooper of Visualize.
So what does that mean?
I think that Kirkland go ahold of Jane's black book (in the link below) http://images3.wikia.nocookie.net/__cb20121126092820/thementalist/images/6/6a/Tumblr_me32umpZrn1rgjl...
Kirkland has been on the hunt for Red John as long as Jane has.  He knows that Patrick is smarter than he is, and wanted to find out who Patrick had narrowed it down to...and when he searched Patrick's room, he found the black book.

Brett Partridge and Jason Cooper are BOTH on that list.  I think that this is the "Fake List" they were talking about in the previews for the next episode.
After Kirkland kills both Partridge and Jason Cooper, that's when Jane realizes what's going on, and tells everybody that someone has his fake list.
Kirkland finds out the list is fake, and takes Patrick hostage to try and get the REAL list from him...

I still don't know for sure who Red John is, but I think I may be right with this theory.  What do you think?

Hey! I think rj is Stilesi rewatched the first episode and I stopped when I saw Lisbon look at where the suspects where, Haffner, Mcallister and either Smith or Stiles where in transit at the time and I don't think they would leave there phone on a bus or anything, Kirkland was too far away, yes he could have left his phone but the next episode kind of rules him out, so that leaves Bertram, and Stiles or Smith , I'm not sure which one is S1 and S2 but I think smith is too short first of all and is overweight and Stiles is the only one it could be because in the second episode of season 6 we clearly see Bertram is on his phone when he arrives, so I think RJ is Stiles!