Around 10 per cent of the electorate had cast their votes in the first one hour.
The main contest is between Akali Dal candidate Joginder Pal Jain and Congress candidate Vijay Kumar Sathi.
Jain had quit the assembly seat and the Congress party on December 26, last year and joined the Akali Dal. He was elected from Moga seat on a Congress ticket in the 2012 assembly polls. His resignation forced a by-election. A total of 10 candidates are in the fray.
A large number of paramilitary forces and Punjab Police personnel have been deployed to ensure free and fair polling.
The security personnel had yesterday held flag marches in Moga town and in the rural areas to instill confidence among the electorates.
During the campaigning, leaders of both the parties launched a no holds barred attack on each other. Although the Congress has lost the recently concluded Assembly polls in Punjab, the party has put all its efforts to defend the seat, which was vacated after one of its leader resigned.