The CPI on Sunday said that it has entered into an alliance with Ajit Jogi's Janata Congress Chhattisgarh (J) for the Assembly polls in the state.
The Chhattisgarh Assembly polls will be held in two phases -- on November 12 and 20. Counting of votes will take place on December 11.
Earlier, the Bahujan Samaj Party had forged an alliance with Mr Jogi's outfit. According to the poll alliance agreement, the BSP will contest 35 seats, while the JCCJ will fight the remaining 55 seats in the 90-member Assembly.
CPI state secretary RDCP Rao and Mr Jogi announced the alliance between the two parties at a press conference in state capital Raipur on Sunday.
Mr Jogi said the addition of CPI to the JCC (J)-BSP alliance had made it a "mahagatbandhan" (grand alliance), boosting its poll prospects in the Bastar region and in places with a high number of labourers.
The aim of the alliance is to form a government which will work in the interest of Dalits, adivasis, the poor, villagers, farmers, labourers and minorities, and take decisions for the welfare of the people of Chhattisgarh, Mr Rao said.
He alleged that over 50 per cent of the state's population continued to live below the poverty line despite 15 years of BJP rule.
Under the agreement, the JCC(J)-BSP will support CPI candidates in Konta and Dantewada, while the Left party and affiliated labour unions will campaign for the former's candidates in Chitrakot and Bijapur in Bastar division and in industrial areas like Korba and Bhilai Nagar, Mr Rao said.
In the 2013 assembly polls, the CPI had garnered just 0.66 per cent of the votes cast and had lost in all the 13 seats it had contested.
Mr Rao, however, said his party had a significant presence in the Bastar region, particularly in Dantewada and Konta seats, from where it has fielded its popular leaders Nandaram Sodhi and Manish Kunjam respectively for the upcoming polls.
While Mr Kunjam has been a two-time lawmaker from Sukma, Mr Sodhi has won the Dantewada seat once in the past.
Mr Jogi will be campaigning for the candidates of the grand alliance in Bastar region between October 20 and 24 during. He will address rallies in Konta and Dantewada on October 23.
The development is being seen as a blow to the opposition Congress which was planning to forge a grand alliance in Chhattisgarh to unseat the ruling BJP.