FIRST of all its not patrick because why would he kill his own wife and daughter. I would say its BRETT PATRIDGE

Red John has to be a main character of the series, otherwise the whole thing would make no sense. Of course there are some clues about Ellis Mars, Partridge, ....., but the usual suspects do not appear in enough episodes to make sure that the average TV-watcher know them. If at the end some guy who emerged in the first season turns out to be Red John, half of the audience do not know him and will be disappointed. 
We can exclude Lisbon and VanPelt, both are women, and probably also Rigsby (sry he is simply to dumb). And would it be surprising if its Cho? Not really...
The only possibility is Jane!! (And forget about the evidences, voice checks, scenes were Jane and Red John meet, ....,every clue can be pointed out in hundred of different ways)
 Its to crazy/unlikely to be true especially because I think he is a very popular character, how ever that could be the opportunity for Bruno Heller to make TV history!!!
AND HERE NOW THE ULTIMATE PROOVE: RED JOHN IS THE OPPOSITE OF PATRICK JANE!!!!
JANE TURNS TO THE MALE FORM OF THE NAME : JOHN
PATRICK, THINK ABOUT ST. PATRICKS DAY: EVERYTHING IS GREEN, AND THE OPPOSITE OF GREEN IS ....... RED!!

HE DID ITT!

please stop with accusing JANE! he is not RJ there is way too much evidence pointing towards other people! and it isn't virgil minelli, whoever RJ is, (if he even works in the CBI which i doubt) has been working there since JAne. the only reason he would be in CBI is to keep an eye on Jane. before Jane there wouldn't be any need to. jesus.

Patrick Jane is a sadist and sociopath. In all his work he takes pleasure in the manipulation and wrath he injects on people. All of his victims (criminals he hunts) have typically done something wrong and are "worthy" and deserving of his punishment. Much like Lucifer himself (who in his return is stated as being a very beautiful and likable person) so is Jane. The sad part is that society sees him as a good guy even when he consistently and continuously dose things to directly and indirectly hurt people. The world is his playground and EVERY sinner is susceptible to his charm and disguise.

Jane was born into this life with many gifts and from an early age he is placed in a position to rip at his morality repeatedly as a means of survival. At some point this behavior normalizes into his personality and eventually he can no longer morally differentiate between what is right or wrong. Knowing the rules and how people react to them however, is like second nature.

As time progresses he deteriorates so much that the few meaningful relationships he has left (wife and daughter) are destroyed because they are considered weaknesses and liabilities.

Logically assembling the pieces to draw a correlation between Patrick Jane and each RJ murder is as difficult as trying to figure out how he manipulates each criminal into divulging that they are guilty. PJ / RJ is playing both sides of the chess board; sometimes directly and other times by putting pressure on people to do his bidding.

It should be noted that the CBI family are a good group who have been infiltrated by a very sick person. Their intentions are GREAT and the things PJ does for them seem like an act from god, so they are willing to accept the means to what they believe is a GOOD end. Unfortunately, this is the state of our criminal justice system today. In fact, it could be easily said that many cops are just as corrupt as the criminals they pursue with the only difference being the power behind them that they wield.

Lastly, Brett Stiles has to be addressed. My gut feeling is that this man is directly linked to Patrick's life development. They are both life long con artists, seem to have a British ethnicity to each (tea drinking, suits, automobile), and seem to each have a deep understanding of the other. Stiles says he knows Red John yet when he looks Patrick in the face he almost arrogantly preys on his divergence. But when push comes to shove he protects Jane (or Red John) just as he would any other flock member in his cult. Jane resents Stiles' as his superior and I believe secretly he would like to take that role from him.

The feds are starting to connect the dots, but Jane always seems to be one step ahead by killing potential witnesses and silencing loose ends before they can leak any pertinent information.

Please feel free to comment. I value feedback and appreciate the thought that goes into it.

Peace to all the Mentalist Fans,

Freespirit

Anyone who thinks its Patrick would have to justify, first of all how he picked himself up off the ground when tied to the chair, why he would have had that stupid conversation with the guy he killed, how he can both be with harker and at cbi at the same time when she calls, why Lorelei didn't just kill him when she found out red John killed her sister, how Kristina fry was abducted while Jane was with people, how he could have a conversation via computer with rj while at cbi, again in the limo, and a whole lot more

I'm not sure about what I'm saying ,
but PLEASE look at the end of season 5 episode 6 , 
Jane look at lorelay's body the look at the wall on Red john's mark and then why he is saying : I'm Sorry ?

why did he say that ? did he kill her or its just because he is sorry .