Mahendran consumed some pesticide at home but his wife and others rushed him to a hospital, where his condition is stated to be out of danger, they said.
Police said Mahendran expected to contest the May 16 polls from Bhavani assembly segment but the party leadership named former MLA K V Ramanathan for the seat.
Reportedly upset over it, he allegedly tried to commit suicide.
Police said a case has been registered in this regard.
