Former Chief Minister Yeddyurappa, who quit BJP and formed Karnataka Janata Paksha late last year, filed the nominations from Shikaripura in Shimoga district, accompanied by a large number of his supporters.
Parameshwara, president of Karnataka Pradesh Congress Committee, jumped into the fray from Koratagere in Tumkur district, and Leader of Opposition Siddaramaiah (Congress) from Varuna in Mysore district.
Former Minister B Sriramulu, who floated BSR Congress after quitting the BJP, filed nomination from Bellary Rural.
The nomination-filing process witnessed a flurry of activities in the State as today is considered "auspicious".
The last day for filing nominations is April 17.
Rajajinagar constituency in the city has attracted considerable attention as former Minister Shobha Karandlaje, a Yeddyurappa loyalist, is taking on sitting MLA and Law and Parliamentary Affairs Minister S Suresh Kumar. Both filed papers on Monday.
Anita Kumaraswamy, wife of JDS state unit President and former Chief Minister H D Kumaraswamy, accompanied by a large group of party activists, filed nomination in Channapatna.
Meanwhile, Kannada actor Rakshita Prem on Monday joined JDS of former Prime Minister H D Deve Gowda, after quitting the BSR Congress, which had given her ticket to contest from Chamarajnagar.
"She has joined the JDS without any expectations", Deve Gowda told media persons after welcoming her into the party fold.
Rakshita said she faced "some problems" within the BSR Congress and there was also confusion in ticket distribution.
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