The party renominated its sitting MPs and former Union ministers, Shashi Tharoor and K Suresh, from Thiruvananthapuram and Mavelikkara Lok Sabha seats.
The Congress replaced Thomas with Hibi Eden, the sitting MLA from Ernakulum.
The party also renominated its Pathanamthitta MP Anto Antony. It fielded former Arunachal Pradesh chief minister Nabam Tuki from the Arunachal West Lok Sabha seat.
The Congress dropped former Union minister and sitting MP from Arunachal East Ninong Ering and replaced him with James Lowangcha Wanglet.
Among the 27 Lok Sabha seats declared Saturday, 12 are from Kerala, seven from Uttar Pradesh, five from Chhattisgarh, two from Arunachal and one from Andaman and Nicobar Islands.
In Kerala, of the total 20 seats, the party is contesting in 16, but has not declared the candidates for the other four seats.
United Democratic Front convenor Benny Bahanan has been fielded from Chalakudy, while Kerala Youth Congress president Dean Kuriakose has been fielded from the Idukki seat.
In Uttar Pradesh, the party has fielded Harender Malik (Kairana), Indira Bhatti (Bijnor), Om Prakash Sharma (Meerut), Arvind Singh Chauhan (Gautam Budh Nagar), Brijender Singh (Aligarh), Pritam Lodhi (Hamirpur) and Bal Krishna Chauhan (Ghosi).
In Kerala, the Congress has fielded Rajmohan Unnithan (Kasaragod), K Sudhakaran (Kannur), M K Raghavan (Kozhikode), V K Sreekantan (Palakkad), Remya Haridas (Alathur-SC) and T N Prathapan (Thrissur).
In Chhattisgarh, the party has fielded Khel Sai Singh (Surguja ST), Laljeet Singh Rathia (Raigarh ST), Ravi Bhardwaj (Jangir Champa SC), Deepak Baij (Bastar ST) and Biresh Thakur (Kanker ST).
Kuldeep Rai Sharma has been fielded from Andaman and Nicobar Islands seat.
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