[2] He was elected as Member of Parliament from the Calicut (Kozhikode) constituency in the General Elections of 1989 by defeating veteran Communist Party of India (Marxist) leader E. K. Imbichi Bava and winning re-election in 1991 by defeating Janata Dal leader M. P. Veerendra Kumar.

In February 2004, Muraleedharan was appointed Minister of Power in the A. K. Antony Ministry, though he was not a member of the Kerala Legislative Assembly.

DIC(K) contested in 17 constituencies but managed to get elected only from one seat mostly because of grassroots level cross-voting by Congress.

Later, Karunakaran rejoined the Congress party, while his son Muraleedharan opted to stay with the NCP, decrying his father's "betrayal".

[8] Muraleedharan contested the 2009 Lok Sabha polls from the Wayanad constituency under the NCP ticket, but came only in third place, behind the Congress party and the CPI.

Subsequently, he won his first assembly election after he defeated ruling Communist Party of India-Marxist (CPI-M) supported independent candidate Cherian Philip by a margin of over 16,167 votes on 14 May 2011.

[12] He was re-elected for the second time in 2016 defeating Kummanam Rajasekharan of Bharatiya Janata Party by a margin of 7622 votes.