"We are 100 per cent sure about the victory of the BJP candidates. Our only concern is how to widen the victory margin," Yediyurappa told reporters here.
Noting that his son and BJP state vice president B Y Vijayendra has been camping in Sira for the past three days, leading the election campaign there, he said he was confident that the party's prospects were bright in the assembly segment.
During the 2018 assembly elections, the BJP had lost in both the constituencies.
On the rains in the state, the Chief Minister said the people of Malnad region were expecting a good harvest this time due to adequate rains while in North Karnataka, the downpour and floods have caused damage to the standing crop.
Yediyurappa said the distribution of compensation to the people in rain affected areas has begun.
Prime Minister Narendra Modi too has assured adequate relief to the flood-hit people of the state, he added.