After casting his vote, he expressed confidence about winning the assembly by-poll and asserted that the main contest was between the Congress and the BJP.
"This by-poll is very important and the Congress will win this election. The contest is mainly between the Congress and the BJP. This is directly parliamentary election," the Delhi Pradesh Congress Committee (DPCC) President said.
"This is a referendum on Kejriwal's two years' work," he said.
According to the election office, voting began at 8 AM and will continue till 6 PM in the area which has around 1.6 lakh electors.
Along with EVMs, the reliability of which has been questioned by the AAP, voter-verifiable paper audit trail (VVPATs) are being used at all 166 polling stations of the west Delhi constituency.