http://www.wickedlocal.com/yarmouth/tvguide/x1281957592/Mentalist-Boss-Bruno-Heller-Breaks-Down-the-...

Red John is definitely Gale Bertram! There are many reasons which were already explained in many theories why Gale Bertram might be Red John. There is an additional clue that as far as I noticed here, has not been mentioned before. Gale Bertram has a an award in his office for bravery in the war.
Carter Peak, the victim that has been killed by Red John and of which Jane assumes that Red John might has made a mistake with him and might have left some trace that could reveal his identy (thus towlen morning his doctor and the bosco team were killed too) was a former soldier in the gulf war.
I am 100% sure you will see in season 6 amongst all this link between Bertram and Peaks revealed and you will see Gale Bertram is RED JOHN.

I don't know why, but I'm really nervous and excited for season 6..I just hope Bruno gets it right, and the actor he chooses plays the part well. My main suspect is Gale Bertram, but I've probably suspected everyone at some point along the way, just like everybody else has. I pretty much have a theory for all the suspects but for some reason I'm getting more and more drawn to McAllister and Smith on the list, just because they were such strange inclusions. People say it can't be one of them because they've only appeared once, but it should be remembered that we had never even seen Timothy Carter before he was revealed and he proved extremely popular....As Heller said anything can happen!
Based on the trailers and gossip we've had for episode 1, I'm going to guess that Bob Kirkland will be the first name scratched off of the list. Roll on Sunday night, I cannot wait! :-)

I have read the following question:

How did Lorelei know that Red John and Patrick Jane shook hands? It seems improbable that Red John told her "I shook hands with Jane". More probable that she SAW this. But the first time Lorelei featured was when she and Jane met at the bar in the episode "The Crimson Hat" (I think). From that point onwards until she told Jane that he and Red John shook hands, was there anybody on the list that Patrick shook hands with, in her presence??

Possible Answer:

Please watch 1st Episode of Season 3: in this Episode Gale Bertram was introduced. In the background there is a woman, who's face is hiding behind a camera. You never see her face. It is the only person you don't see the face of. I think this was no coincidence, dear Bruno!! ;o)))  The woman looks like Lorelai (it could be Lorelai). After that Bertram and PJ shake hands. She could have seen it. But that means, Gale Bertram is RED JOHN.

Another theory:

Why a fake Red John at the end of season 3? Because PJ met the true Red John just before. Fake Red John to cover true Red John!!! That would also mean, that Bertram is RED JOHN. 

By the way, I don't like the idea of Bertram as Red John.

My favorites:

Brett Partridge or
Sheriff Thomas McAllister :o)))

He sang the "Tiger Tiger" poem under his breath in an older episode. He's has great people skills and this whole time has been playing the CBI. He also has high connections in the FBI.

If Heller goes for the logical then we are left with 2 choices: Bret Stiles or Gale Bertram. Kirkland wants RJ to boost his career. Haffner was too easily fooled by Jane. McAllister also when they played Paper, Scissors, Stone. Reede Smith is too vague. Partridge too obvious but was in the Pilot episode. However, as brought up earlier by others, surely Heller should've had actual on-screen hand shakes for the Lorelei clue right!? If so, just Haffner and Bertram shook Jane's hand but Lorelei was incarcerated when Kirkland shook Jane's hand. She'd not know about him shaking hands. So, Stiles has never shook Jane's hand and that leaves Bertram. Recites Blake, was at the scene of Johnson murder, sounded like RJ and called Jane The Boy Wonder (thus knowing Jane's Carny past) so he is the logical choice. Thoughts?

I think that everybody overlooks something very important when considering the seven suspects on hand...this being that whoever Red John may be isn't going to be Red John in their every day life...if Red John is truly a mastermind like Jane he will have the uncanny ability to convince people that he's someone he's not....Brett Partridge, for example, could be Red John simply hiding his charming personality from the world that knows him as Brett Partridge...the same is true for the remaining six suspects. I think that when you look at it from this perspective it is impossible to narrow your list down...and when you think about it, the least likely a character is to be Red John...the more interesting a hidden side to that character could be. And example in mind is Gale Bertram. Next time you watch in episode in which Bertram speaks, imagine a high pitched, soft Red John voice. Imagine the way he acts as a scheme such as many of the ones that Jane pulls in which he's hiding who he really is in order to outsmart everyone else. After watching the season 4 premiere, I'm far more intrigued by the idea that Bertram could be Red John. But then again, anyone could be Red John if the writers want them to be...its only a matter of creating two characters in one. This is less of a theory and more of an observation...but consider it next time you compare each suspect to Red John.