The party, which ruled Bengal with a near-absolute mandate for 35 years, suffered a humiliating defeat at the hands of arch rival Trinamool Congress in 2011.
Since then it had tried to stage a comeback by organising programmes which at best evinced some lukewarm support.
The scenario changed for the better last month when it organised two successive programmes. First, the Left Front sponsored peasants' march to the state secretariat on August 27 and second, the "successful" implementation of the countrywide general strike in West Bengal on September 2.
Bose said, "When a government comes to power with a massive mandate, the masses want to give them some time. But when after four years things do not move rather the situation has worsened, people have realized the true colours of TMC."
"After 2014, a large section of the media had completely erased us as opposition, but the results and the recent successful political movements have shown that we are still the only alternative to the misrule of the Trinamool Congress," Salim said.
Attributing various factors, including the change of leadership in the state CPI(M) and the ongoing massive rectification drive within the party to the "turnaround", a senior CPI(M) leader said the TMC's silence over the alleged anti-people policies of the BJP government too helped.