We have covered Red John to be the 7 suspects, Jane himself, the CBI gang, Mashburn, Red John is gay, the pigeon flying in the barn 

The only theory left, is that RED JOHN is Loerlei Martins

"He is Mar" can be He is Martins, RJ probably had sex change or Renfrew has never heard of Wren and Martin whatever, it's fiction after all.

Bruno Heller has said, that Red John is the Keyser Soze (of the Usual Suspect Kevin Spacey fame) of Mentalist.

What if Loreloi was Red John afterall? And she built up this fake image of Red John.

Red John loves Jane more than himself now, according to one of the theories that I read.

Lorelei Martins is coming back in Great Red Dragon.

If this is not crazy enough, then please read my other theory

http://www.whoisredjohn.com/See-a-theory-Red-John/11591

It's crazy! But isn't Mentalist about being crazy. What say?