New Delhi: The saffron surge in West Bengal in the 2019 Lok Sabha polls has put the political legitimacy of the state' ruling Trinamool Congress at stake, analysts said on Thursday.

They also said that the BJP could come to power in the 2021 Assembly polls, or even earlier, by ousting the Mamata Banerjee-led Trinamool government in the state.

"The BJP's rise is all set to bring structural changes in the state politics. Prevailing political narratives like secularism and welfare of poor were developed by the Left Front, while the Congress and Trinamool mostly followed the same," political analyst Bimal Shankar Nanda told .

"If the BJP manages to win more than 15 seats, political legitimacy of the Trinamool government would be at stake."

He said there "could be repetition" of what happened in the last two years of the erstwhile Left Front regime after most their candidates lost in the 2009 Lok Sabha polls. Eventually, Trinamool swept to power in the state in 2011.

Amid apprehensions of losing seats in the cow belt, the BJP made a strong pitch to woo voters in West Bengal and increased its vote share on the back of the rising popularity of Prime Minister Narendra Modi, polarisation, and exploiting issues like nationalism.

Moreover, the BJP also got the help of leaders that the party poached from the Trinamool Congress, analysts said.

According to one, the BJP's new narratives of nationalism and its campaign of "no appeasementa to any particular community have clearly paid dividend to the saffron party in the eastern state."

"There has been a massive polarisation in West Bengal and it would not be surprising if the BJP comes to power in 2021 or even before, ousting Trinamool government," political analyst Udayan Bandyopadhyay told .

According to analysts, the BJP's relentless attacks on the Trinamool supremo, accusing her of appeasement politics, helped polarisation in the state and the consolidation of Hindu votes.

"Trinamool Congress introduced a model of development in the state although it was widely criticised. In spite of the development work undertaken by the Mamata government, Hindus, who comprise over 70 per cent of electorate, felt let down in the state and believed that they were deprived of the fruits of development," Nanda said.

The latest trends suggest that Trinamool Congress is leading in 21 seats while the saffron party was ahead in 20 seats.

Trinamool had won 34 Lok Sabha seats and the BJP bagged only two seats in 2014.

Some policies of the Trinamool, like offering stipends to Muslim clerics and special arrangements for the minorities in areas like education, have been given a "thumbs down" by the voters.

"Such appeasement politics created doubts among Hindus on whether the state government is favouring Muslims more. Banerjee too acknowledged indirectly of her party's appeasement policy towards the minority community as she started chanting mantras during campaigns to woo Hindus. But it was too late," Nanda said.

The shift of the Left vote in the state to the Right, which has been debated intensely, is largely the result of "Mamata's suicidal strategy" to ruin the Left parties in the state.

The party-wise vote share clearly shows that the Trinamool Congress suffered from the sharp drop in the Left Front's vote's share to below 10 per cent. The Left Front vote share was over 29 per cent in 2014 and fell to about 22 per cent in 2016.

In 2014, the BJP, despite its weak organisational strength in the state, managed to increase its vote share to 17 per cent, which came down to around 10 per cent in 2016.

Analysts, however, said the BJP's challenge would be to project a leader to match Mamata Banerjee in the 2021 Assembly elections.

According to them, Modi may have done it for the party in this election, but for the state polls the BJP needs to find a good chief ministerial candidate.