Voting began on Monday in the by-election to six assembly constituencies in five states and the Mainpuri parliamentary seat in Uttar Pradesh. Rampur Sadar and Khatauli in Uttar Pradesh, Padampur in Odisha, Sardarshahar in Rajasthan, Kurhani in Bihar and Bhanupratappur in Chhattisgarh are the assembly seats where the bypolls are being held.