I'm back and forth on this one. From everything I've seen the arrows are pointing to Bret Stiles. Lorelei said she was surprised they weren't best friends since they shook hands. I'm assuming (correct me if I'm wrong) that they shook hands. She says they are just alike, manipulative etc... and on the description of the first episode Stiles in it says "Patrick finds a new adversary in a charismatic but manipulative cult
leader while the CBI team investigates the death of the CEO of a media
conglomerate."
Two traits strongly attributed to Jane and being a cult leader takes a level of charisma and manipulation that would be required to establish this power base he has which seems to reach to high levels of law enforcement.
It would also explain why he was hesitant about Jane breaking Lorelei out of prison. One, he might turn her but Stiles might view that as just another challenge in this game between them. Second and more importantly, if Jane was captured and arrested it would put a huge stall or complete stop to Red John's game.
Stiles is the only character I've seen that has shown the intelligence and other various qualities and characteristics required to be Red John, but that is where I become hesitant. At this point it seems a little to obvious and I have a feeling the writers want to shock us with who he is but Bret Stiles wouldn't shock or surprise me at this point.
