For Chief Minister Mamata Banerjee, the BJP advent is no cause for worry yet.
For the BJP, which had to cede space to the Congress in Gujarat and Rajasthan, there was some cheering news. After 15 long years, the party has finally managed to open an account in Mamata Banerjee's West Bengal, with the Basirhat Dakshin seat. (
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But it has lost its key target - the prestigious Chowringhee in Kolkata, which the Trinamool Congress has managed to retain.
The BJP last held an assembly seat in Bengal in 1999 - when it was an ally of the Trinamool Congress. The party has two Lok Sabha seats in Bengal.
But now, its victory in smalltown Basirhat, which belonged to the CPM, may come as a disturbing trend for Ms Banerjee -- especially since the rural areas in the seat are minority-dominated.
Chowringhee was won by Nayana Bandyopadhyay - wife of senior Trinamool leader Sudip Bandyopadhyay - who beat BJP state secretary and spokesman Ritesh Tiwary.
The seat was won by Sikha Mitra of Trinamool Congress in the 2011 assembly elections. The by-election was held after it fell vacant when Mitra resigned from the party.