Alright, forgive the grammer, I think it's Virgil Minelli because RJ has to be someone who is older than PJ by close to 20  years because in season 1 episode with Rosalind Harker (Alicia Witt as the blind woman who plays piano), the cop at the end tells him that RJ was a friend of his dads a long time ago and the cop was at least 30, making his dad at least 50 (probably).  As the Director of CBI and Lisbons boss, he was the one who hired Jane in the first place and he's able to watch over his pursuit of RJ in the beginning. 

After he leaves the CBI, he assists PJ with tracking down RJ associates, and as a cop he would be privy to investigative techniques too.  RJ is obviously just as smart as PJ if not smarter (Holmes and Moriarty anyone?), and could easily tone down his intelligence around PJ if he wanted.  He's also divorced and has plenty of free time now.  Sorry I'm light on facts but have had a gut feeling about him since the end of season 1

Eventhough Minelli isn't one of Jane's 7 suspects, I believe Jane is hiding his real list, and came up with a fake list which was some-what predictable that Red John could have guessed. The reason he didn't tell Lisbon his real list is because he thinks Lisbon is a terrible liar as he has mentioned many a time throughout the series. But anyway back to my theory of it being Minelli, in season one, it is very coincidental how Minelli leaves to go on holiday during Renfrew's death. This may be a bit far-fetched but hey. Furthermore, as Renfrew was dying he wrote "He is Mar" There has been some speculation saying that this could have been referring to Ellis Mars, however Jane and the team did not know of Ellis Mars until season 4 and frankly it would be difficult to identify a serial killer based on a second name this is quite popular. I think that Renfrew was trying to say "Marnelli" and Renfew being Renfrew spelt his name wrong. 

Come on
people! There are some ridicoulus theories here :D 

The guy with his tongue cut off is not connected to RJ in any way in my
opinion. He is just trying to say something and I'm pretty sure it's some
random words. I don't hear anything like "it was him red john" haha.
It's just closure to the episode and Lisbon is realizing what's in the
tupperware box.

Another
thing – why shouldn’t we all be excited about upcoming season finale? I think
it would be very intense and the fact that Jane has a list of 7 suspects is not
the whole point of the episode :P Actress playing Lisbon said that the episode
would be surprising. There would be some twist for sure and some new
information about RJ maybe. Of course there also should be massive cliffhanger
to keep us through summer! So I’m really looking for it.

As for RJ
my money is on Virgill. It would be very interesting and not disappointing
solution at all for me. It would be cool to rewatch the episodes with him (and
there are so many!) and catch little clues that were there all the time. I see
RJ as some older guy like Virgill and a little bit of oldschool (season 1
finale, the farm and all this stuff in the house). It’s more like Seven or Saw
kind of mood than some ultra rich guy, Lamborghinis and women (Mashburn kind of
guy) if you know what I mean. Also his conversation with Patrick on the pier is
a clue for me. It can be understood in two ways. When Patrick told that for one
time he has advantage over RJ and Minelli said “You sound nuts my friend” that
would be awesome if he is RJ. And also conversation about Dorothy from Cansas
and Patrick asking If I’m Dorothy then who are you? And Virgil’s answer It
doesn’t matter who I am J It could have no meaning at all but on the
other hand it could that’s why it is so good RJ for me. He could also have a
lot of money and connections which are not explained or show. He also likes
fishing like the guy Lorelai shot. A lot of clues really if you think more
about it or maybe red herrings :D

My second
suspect is Jason Cooper ;D Not much history but it would be also nice. And the
hug Jane gave him what was all this about? He may be testing his suspects
really subtle how they react and surprising them.

Max Winter
could be good Red John too. There are really some possibilities for writers and
it’s cool.

Gale
Bertram would be surprising but disappointing for me. Kirkland no way he is
definetely shown this way to throw us off track it would be to easy. There's
another story besides him but he is not RJ. Anyway take care!

Who say that Patrick Jane is Red John ; it is non-sense. I don't think so that the scnerio is about someone who killed their own family.I think Red Joh is ; Virgil Minelli. Because he is close to everyone and head of CBI.Therefore Minelli brougt Jane to CBI for consultant.Whereby he plays with Jane.

I'm not 100% but one fact that seems to support Minelli as a suspect is that Lisbon has remained unharmed to this day. Being as close as she is to Jane, it's a wonder she has not become an RJ victim by now. But Minelli and her were close and seemed to have a father-daughter bond so that may explain her relative safety. And that threat to Jane..to bring Lisbon's body with him? I don't think RJ every believed Jane would go through with that anyway so it was an empty threat on RJ's part.

lets really think about it . the whole objetive of the series is to find red john, and it has been like that ever since the begining of the series, from season 1. this can only mean one thing. in tv series, we generally see the three main characters at the begining. who are the main characters of TM? . Patrick Jane, Teresa Lisbon, and off course, Red John. what does this mean? that if the point of the series is to find Red john, that means that he has been under our noses all the time, SINCE SEASON 1. red john appeared in every episode of season, his importance in the series gives him the need to appear in season one. my guess, Virgil Minelli. Another thing, what happened to Brenda since we saw that she was corrupt and allied with Tommy Volker? i have the feeling that is not the last we will see her. she might be also be friends with RJ.

I went to chapter 2x08, following a lead (that turned out to be nothing) from a previous poster, and in minute 23, there is a scene where patrick jane says to the forensic doctor " lets finf out what this agent rojo ( red in spanish ) looks like, and they havent even finishing saying rojo when theres a change of scene and we get a closeup from minelli for about 4 seconds watching photos with a grim face.

Theres a lot more reasons that only this scene to accuse minelli, but knowing the directors, this kind of small things is what they like to throw at us as "clues" if you have time or if you are interested enough, check it out, is rather suspicious.