The workers were constructing a toilet at a school next to the temple in Faridpur’s Madhukhali Upazila
Hathazari OC Md Ismail said the incident occurred late Thursday night.
Victim Noor Elahi Jewel, 35, son of Mirjapur Union’s Sheikh Ahmed, had gone to campaign for Awami League candidate Nurul Absar, an aspirant in the UP polls.
The Mirjapur Union Parishad goes to polls on Saturday.
Ismail said that a grievously injured Jewel was rushed to Chittagong Medical College Hospital.
He was declared dead by the doctors attending on him.
Police could not immediately ascertain how he was hit by the bullet.