The election process in Madhya Pradesh's Betul Lok Sabha constituency was cancelled after the Bahujan Samaj Party's (BSP) candidate died on Tuesday, an official said.
Ashok Bhalavi, the BSP candidate from the seat, died in the evening.
The polling in the constituency, scheduled for April 26, was consequently postponed, district collector and returning officer Narendra Singh Raghuvanshi told PTI.
Under the provisions of the Representation of the People Act, the election process was stopped and further action will be taken as per the directives of the Election Commission of India, he added.
Dr Manish Lashkare, who runs a private hospital, said the BSP leader suffered a heart attack and he was dead by the time he was brought to the hospital.