This is a previous theory:

For those of you who think Red John is one of the remaining 5:
Rigsby says "Red John brought in the bomb to kill Jane and the other suspects"
If any of those 5 were Red John, why would he plant a bomb in a room that he was going to be in, just to kill himself, Jane, and the other suspects?
Answer: they wouldn't. There would be no point for Red John, this extremely prideful, narcissistic, showman of a serial killer, to plant a bomb to kill himself and his nemesis, along with a few others. Really, if you were Red John, would you waste 20 years of killing people just to die in an explosion with no one knowing that you were actually Red John? No, you wouldn't. You would make sure that, if you were going to die, everybody would know who you were so you would leave a lasting effect on them.
And if it is true that Red John is on the list of 7, then we can eliminate the 5 ones that are definitively alive because of the explosion. That leaves Bob Kirkland and Brett Partridge. Bob Kirkland is definitely dead, we saw him get shot in the back 7 times. That just leaves partridge.

Ok this got me thinking we know partridge is dead SO the only possible explanation IS Bob Kirkland IS ALIVE (or is it his twin!)

When he asks "do you know who I am" to people he is seeing to try to find his brother who was apparenty taken under Red John's wing a long time ago. But what if the old red john stopped killing because he died (which is why red john was said to stop killing for a few years) then Kirkland's twin brother took over as "red john" ? It makes perfect sense! We were told by the producer of the Mentalist that the list is 100% legit meaning red john IS 100% someone on the list! Kirkland's twin brother is Red John! Please comment to share you're thoughts!