I don't believe any solid identity can be linked to Red John. I am currently catching up (I'm at season 3 episode 12) but at the stage I am at I have reason to believe as of yet he has not been revealed yet. 

My personal opinion is that Partridge is involved and could be Red John's right hand man, the mole inside CBI. It may very well have been Partridge who saved Jane at the end of season 2.  But I do not think this is Red John.  

I will run through my thoughts so far and I appreciate anyone who wishes to speak about the subject to contact me on Jake.Muso@gmail.com.

1) CBI Ron : No, it's not Ron. Would have been interesting but Ron is too much a part of the back ground to be Red John. He seems genuinely not interested in Jane or the team and there would at least have been baleful glance in Patrick's direction at some stage just to annoy watchers into adding him as a suspect.  Accusing him is like accusing a chair on the set. He's part of the furniture.

2) Brett Stiles : I get the feeling that he is most definitely part of the Red John plot.  He basically admitted to it without admitting to it if you know what I mean.  BUT he is not Red John himself.

3) Lisbon, Van Pelt, Cho, Rigsby : In my opinion there is no chance of any one of them even being involved.  There were stages where I believed that Lisbon may be, but her latest behaveour rules her out of it for me.

4) Mashburn : I don't really know about him.  He is a wild card.  But in the end he brags a lot, and he is very annoyingly outspoken.  I wouldn't rule him out as a suspect just yet.

5) Patrick Jane : The notion of him being Red John fits the profile except for the fact that he and Red John are often in two very different places.  I don't see this happening ever.  

However I am trying to look through each and every character to see which person matches Jane in character and skill. Look out for sharp observations by someone other than him.  Because we know they are very alike.  They read the same poetry, they both drink tea, they like playing mind games to defeat their adversaries. Plus if you look at the poetry used i.e. Tyger Tyger.  This is written by William Blake.  In season 3 we see Patrick reading another poem by William Blake.  William Blake believed in Heaven and Hell reconciling and becoming one.  Almost like Yin Yang where the dark and light is one and the same.  Plus the poem speaks of 'fearful symmetry'. This says one of three things:
1) Symmetry as in one object divided into 2 parts which are the same : Making Patrick Jane Red John.
2) The same on one side as there is on the other : Almost like an evil twin somewhere of Jane.  Identical just very bad.
3) As in number 2 there is someone exactly like Jane running the Red John saga.  Someone with the exact same skills etc.  

Plus don't rule out his dad...