Thangaraj died at the Government Hospital in Erode, about 50 km from here, where he was admitted after he set himself ablaze on November 18, police said.
A case has been registered against the AIADMK Namakkal women's wing secretary Kalyani for allegedly abetting the suicide after the victim gave a dying delcation before a Erode Magistrate, they said.
Police said the woman was absconding and further investigation was on.
Upset over this, Thangaraj allegedly doused himself with kerosene in front of Kalyani's house and set himself ablaze.