Polling was peaceful in all the constituencies, electoral officials said, giving the voting percentage at the end of the exercise as Chikkodi-Sadalga (81.30), Bellary Rural (68.9) and Shikaripura (65).
The three constituencies have a total electorate of over 5.57 lakh.
For Chief Minister Siddaramaiah, a lot is at stake as he faced the first popularity test after Congress' not so impressive show in the Lok Sabha polls in which it managed to secure only nine of the 28 seats against a resurgent BJP's 17.
A good show in today's by-polls would be a booster for Siddaramaiah to consolidate his position in the party, where there are signs of discontent with the functioning of his government.
More From This Section
The by-elections are also a litmus test for BJP National Vice-President B S Yeddyurappa, whose son B Y Raghavendra has been fielded from Shikaripura, his stronghold which he had won seven times. The seat fell vacant following Yeddyurappa's election to Lok Sabha from Shimoga, which Raghavendra earlier represented.
The by-poll to Chikkodi-Sadalga was caused due to the election of Prakash Hukkeri to Lok Sabha from Chikkodi.
Congress went all out not only to retain Chikkodi-Sadalga but also wrest from BJP Bellary Rural and Shikaripura.
JDS, dogged by rumblings of discontent within over the leadership of its supremo Deve Gowda and his son and former Chief Minster H D Kumaraswamy, has not fielded any candidates.