Jitin Prasada served as a cabinet minister of PM Manmohan Singh in 2018.
BJP had claimed that 14 of its workers have been killed in the post-poll violence.
BJP's national president JP Nadda will visit West Bengal on Tuesday.
Security measures have been tightened in view of the violence during the previous phases.
In the fourth phase of voting, 373 candidates including film stars and celebrities are in fray.
Mamata Banerjee has written a letter accusing the BJP of attacking democracy and constitutional federalism.
The voting started at 7:00 AM and will run till 6:30 PM.
The ruling party Trinamool Congress (TMC) has announced candidates for 291 seats on Friday.
Actor Arun Govil, known for playing the role of Lord Ram in the TV serial 'Ramayana', has joined BJP today.