Thiruvananthapuram, May 3 (IANS): The CPI-M on Thursday said it will retain the Chengannur seat in the May 28 bypoll as it promised drubbing of the opposition, saying the Congress-led UDF will become a non-entity in Kerala politics.

The Communist Party of India-Marxist candidate for Chengannur bypoll will not just retain the seat but will win with an increased margin, said party secretary Kodiyeri Balakrishnan. He said there was no doubt over the outcome.

"The Congress-led United Democratic Front's popularity is on the wane and our aim is to ensure that they become a non-entity in Kerala politics.

"If you look into the constituents of the UDF at the 2016 assembly polls, they have already suffered serious reverses -- as the Janata Dal-United (JD-U) has left them and joined us, while the Kerala Congress (Mani) is now not with them and they are not campaigning for the Congress candidate," said Balakrishnan.

The bye-election was necessitated by the death of CPI-M legislator K.K. Ramachandran Nair in January.

By winning Chengannur in 2016, the CPI-M breached the Congress fortress of a quarter of a century.

Nair secured 52,880 votes, Congress candidate P.C. Vishnunath 44,987 votes and the BJP candidate P.S. Sreedharan Pillai 42,682 votes.

The CPI-M candidate for Chengannur bypoll is their Alappuzha district secretary Saji Cheriyan. He had in the past unsuccessfully contested the polls.

Congress has fielded party leader D. Vijayakumar, and the Bharatiya Janata Party has retained Pillai.

Balakrishnan pointed out that the election will not just be an evaluation of the Pinarayi Vijayan government but also that of the Union government.

He said his party will seek the votes of all, except the Rashtriya Swayamsevak Sangh.