Huge white boards and posters were displayed in Gadaulia where people were asked to sign if they thought Modi should contest the general elections from the constituency.
The BJP workers, under the name of 'Modi Army', said they will take five lakh signatures and send it to the national leadership for consideration.
The campaign comes a day after senior BJP leader and the incumbent MP from Varanasi, Murli Manohar Joshi's posters were plastered all over the city.
Joshi earlier contested from Allahabad but was sent to Varanasi 2009.
The party's parliamentary board is likely to take a call on the candidature from Varanasi in a few days, according to party sources.