Early political career After
Kamaraj's demise, some of Radhakrishnan's family members joined the
Janata Party. Radhakrishnan's brother Ramakrishnan joined the
Hindu nationalist Jana Sangh and took charge as the district chairman. Radhakrishnan's uncle Chidambaram Athiswami Nadar contested and won the
Colachal constituency in the 1977 elections on behalf of the
Janata Party. In 1981, Radhakrishnan joined a
Rashtriya Swayamsevak Sangh (RSS) and later became its secretary. Later, Radhakrishnan's father Ponnaya Ayyappan was elected as the District President of
Vishwa Hindu Parishad (VHP). Radhakrishnan was defeated by a CPI (M) candidate in the Nagercoil Lok Sabha constituency in 2004, and in 2009, he was beaten by a DMK candidate in Kanniyakumari Lok Sabha constituency.
As minister and political career (2009-2019) He was president of
Tamil Nadu state unit of the
Bharatiya Janata Party, resigning the position when he became a Minister of State in the
Narendra Modi-led government. He had won in a Lok Sabha seat in the
2014 Indian general election, from
Kanyakumari constituency by a margin of 1,28,662 votes. During this tenure, he served as Minister of State in various portfolios like Heavy Industries, Shipping and Finance.
Politics (2019-present) In September 2019, Radhakrishnan created a controversy after calling Tamil people as 'ungrateful'. He explained that the Tamil people failed to celebrate Modi after he praised the Tamil language. Later he claimed that he did not call all Tamils as ungrateful and only those doing politics with the language. Pon. Radhakrishnan participated in a BJP rally in support of
Citizenship (Amendment) Act, 2019 in Nagercoil in March 2020 where he spoke of chasing away
Christian priests from the district. Many demanded that action be taken against Pon. Radhakrishnan for his communal speech which can incite violence. Police complaints were also filed against him. Fishermen in Kanniyakumari claimed that around 40,000 - 45,000 fishermen votes in the 48 coastal hamlets in Kanyakumari Lok Sabha constituency was deliberately removed from the electoral-list out of fear that the fishermen would vote against the lone BJP Union minister, Pon Radhakrishnan, contesting in the constituency during the 2019 Lok sabha elections. The coastal fishermen also complained that votes of inland fishermen in another 68 villages also have been removed purposely. They also alleged that their names were removed only a few days before the day of polling. He lost the Lok Sabha elections in 2019 by a margin of 2.59 lakh votes to
H. Vasanthakumar from Indian National Congress. After the death of Vasanthakumar, he again contested in 2021 Lok Sabha by-election. But he was defeated by a margin of 1,37,950 votes by
Vijay Vasanth who is the son of late Vasanthakumar. He again contested in
2024 election and lost again. ==Political views==