After winning a bitterly-fought battle with the BJP to record her third successive victory in the West Bengal Assembly elections, Trinamool Congress supremo Mamata Banerjee seems to have emerged as a formidable challenge to the Centre's ruling party.With leaders of different regional parties, including NCP chief Sharad Pawar, sending her congratulatory massages, the message from the Assembly election is clear that Banerjee is capable of taking the challenge of Prime Minister Narendra Modi and Home Minister Amit Shah, and combating it successfully.However, the Congress, which was expected to win at least two states but could not do, failing to wrest Assam from the BJP and Kerala from the Left, still insists that it is the only option to BJP.Congress chief spokesperson Randeep Surjewala said: "Congress is the sole national party which is alternative to the BJP as it is fighting BJP in all the states."But the messages from the leaders of regional parties indicate that Banerjee, whose Trinamool which was once part of the UPA, has shown her mettle by single-handedly defeating the BJP and in a convincing manner.The poll results show that people of West Bengal have rejected the Bharatiya Janata Party's attempt to polarise the elections. The BJP, which had left no stone unturned to dislodge the Banerjee government, could not cross three-digit figure despite its claims of getting 200-plus seats out of the state's 294.The reason behind Banerjee's masterful performance was admitted by a BJP leader, who said that their leadership "failed to understand the pulse of Bengal and its culture". "And that is the reason despite leading in 121 Assembly constituencies in the 2019 Lok Sabha polls, we are facing difficulties in winning over 100 seats in less than a two-year period.""People rejected politics of polarisation or communal politics. Muslim votes polarised in favour of the Trinamool while the Bengali Hindu also rejected communal politics and voted for the Trinamool," the BJP leader said.