"Historically, the party has been changing colours. Splitting from the Janata Party to become the WBSP and then joining the SP, later withdrawing and then rejoining, they have been continuously changing their stand.
"Their (SP) move to field candidates has been fuelled by the Trinamool, which without caring about legitimacy, has been trying everything to intimidate its opponents," Salim, a Front candidate from Raiganj, told IANS.
Raiganj (North Dinajpur) is one of the four constituencies where the SP has fielded candidates, the others being Maldaha Uttar (Malda), Birbhum and Barasat (North 24 Parganas).
Ever since it was dethroned by the Trinamool in 2011, the Front has fared poorly in electoral battles - be it at the rural level or for the civic bodies or even the by-polls to assembly seats.
Political analyst Anil Kumar Jana believes the SP's departure days before the polls will adversely affect the fortunes of the Front.