BJP's sharp focus on the state, and efforts of PM Modi and Amit Shah seem to be paying the desired dividends. The party has increased its vote share to nearly 40% from just 17% in 2014. The Left, that cornered almost 23% votes in 2014, saw its vote bank gravitate towards the BJP, which is now being seen as the principal opposition to Mamata Banerjee's TMC.

from Times of India https://timesofindia.indiatimes.com/india/crumbling-left-depleted-cong-helps-saffron-surge-in-mamatas-bengal/articleshow/69464225.cms