"We had issued show cause notices to 30,000 voters on why their names should not be deleted. But only one per cent among them responded and their cases were disposed off accordingly," said Returning Officer Narendra Fulzele.
He said the names were deleted mainly on grounds of death of some voters, repetition and shifting from their place of residence.
Fulzele said remaining 10,000 names probably got deleted during revision of electoral rolls by a Bhopal-based private concern which was awarded the contract to prepare final voters list.
He, however, admitted there could be a "lapse" at the local level.
Congress stalwart Shivajirao Moghe and sitting Shiv Sena MP Bhawna Gavli were the major contenders.