The list of RJ suspects :

1. Reed Smith - Judged by Patrick Jane and he believed that he's not Red John.

2. Gale Bertram - He's one of the top member of Tiger Tiger Organisation and he told Patrick Jane many times that he wants to be there when he finds Red John. He's running from everyone, taking his cash and no proper planning. He's not Red John for sure.

Now the remaining 3 suspects presumed to be dead by coroner.

Lisbon found a foot in Jane's house which seems to be either Haffner's or McAllister's.

The writer of the show didn't confirmed that all 3 are dead but he confirmed that there are deaths from the explosion.

The show is made in such a way that no one will accuse Bret Stiles.
He's definitely Red John.

Please comment if you want to say something.