Ramachandran was the
Dravida Munnetra Kazhagam (DMK) student secretary while at Annamalai University. As a secretary, he organised DMK meetings at
Arignar Anna would be the prime speaker. Anna was impressed by Ramachandran's government of Tamil Nadu he used to speak as Sampath in DMK public meetings. He named his son as Sampath after his pen name. He started his political career as a DMK member. He was the Minister for Transport of Tamil Nadu during 1971–77. He later joined
Anna Dravida Munnetra Kazhagam (ADMK). He has won six assembly elections contesting from
Panruti constituency. He was elected to the
Tamil Nadu legislative assembly from
Panruti constituency as a
Dravida Munnetra Kazhagam candidate in
1967, and
1971 elections as an
Anna Dravida Munnetra Kazhagam candidate in
1977,
1980, and
1984 elections and as a
Pattali Makkal Katchi candidate in
1991 election. The chairman of the
Desiya Murpokku Dravida Kazhagam presidium and Deputy Leader of the Opposition in the Tamil Nadu Legislative Assembly, Ramachandran on 10 December 2013 announced retirement from active politics. In his letter addressed to DMDK founder-president
Vijayakanth, he stated that he had taken the decision as he had been maintaining indifferent health and his doctor had advised him to take rest. He resigned from the DMDK and in February 2014 he joined the
All India Anna Dravida Munnetra Kazhagam party. He blamed the abnormal distance formed between the DMDK and him. After that he spoke in many Constituencies for the AIADMK Victory in 16th Lok Sahba Election. In 2005 he received
Periyar Award and in 2013, the Tamil Nadu government honoured him with
Arignar Anna Award. ==Electoral career==