New Delhi, Feb 27 : The CPI (M)-led Left Democratic Front is going to give a tough fight to the Congress-United Democratic Front coalition and the Bharatiya Janata Party in the upcoming assembly elections in Kerala, as it is likely to win 87 seats out of 140 and have a vote share of over 40 per cent, the IANS-CVoter survey revealed on Saturday. On Friday, the Election Commission of India announced the poll schedule for the Kerala Assembly election. The state will vote in a single-phase election for all 140 seats of the Kerala Assembly. It is likely to be a hotly contested political battle. In 2016, the LDF had assumed charge. According to the survey of more than 8,796 participants taken in six weeks, the LDF may have a vote share of 40.1 per cent as against 41.9 in the 2016 elections. It may score 87 seats, down by four. The Congress-led United Democratic Front will gather a vote share of 32.6 per cent, in comparison to 2016, when it logged 38.8 per cent. The seats will increase from 47 to 51. Notably, Bharatiya Janata Party's vote share will plummet from 14.9 per cent in 2016 to 12.7 per cent in the upcoming elections. The seats will, however, remain constant at one. Kerala, for long, has remained an unconquerable fortress for the BJP. The surveyor asked the participants who they will vote for if the assembly elections are held today? To this, 40.1 per cent said that they will vote for LDF, 32.6 per cent for UDF, while 12.7 per cent said BJP. In the outgoing Assembly, the CPI-M-led Left Democratic Front had 91 seats, while the Congress-led United Democratic Front had 47, and the BJP and P.C. George, whose party is not allied with any of the three fronts, had one each. The LDF comprises 14 parties, including the Kerala Congress-Mani and the erstwhile Janata Dal-U (now the Loktantrik Janata Dal), which crossed over from the UDF last year. In the UDF, there are just five parties at present, and while the BJP-led National Democratic Alliance also has five, the others, apart from the BJP and the Bharat Dharma Jana Sena, have just a nominal presence. /IANS