Congress fielded Arun 'Mickey' Dogra from the seat while BJP pitted Sukhjeet Kaur, the widow of party MLA Amarjit Singh Sahi, against him.
Sahi represented the seat in the state Assembly before his demise earlier this month which necessitated the bypoll.
Kaur's name was finalised by BJP President Nitin Gadkari on the basis of recommendations of Punjab's State Election Committee.
"Congress president Sonia Gandhi has approved Dogra's candidature," Punjab Pradesh Congress Committee chief Capt Amarinder said in Chandigarh.
Dogra is the son of former Punjab minister Ramesh Chander Dogra, who had represented Dasuya constituency a number of times but had lost the last assembly poll to Sahi by 6,223 votes.
