In the 2021 West Bengal elections, the Trinamool Congress has faced its greatest challenge to date and has emerged with its strongest performance ever, both in terms of seats and vote share. With nearly 48% of the votes and 213 seats, the party improves on all its past performances (three seats remain to be contested).

In this article, we use the Trivedi Centre for Political Data’s unique Indian Elections Dataset, derived from the Election Commission of India’s preliminary results (as published in the morning of May 3), treated and expanded by the TCPD team. We examine various measures of parties’ performance and place them in a historical context.

In the following chart, we compare the performance of major parties and alliance in the 2016 and 2021 election. We also include the 2019 results, split in assembly. This shows that even though the Bharatya Janata Party improved its presence in the state assembly compared to 2016, with 77 seats for 38% of vote share, this election is a setback compared to its 2019 performance, in which it won in 121 assembly segments, with 40% of vote share. A small decrease in vote share led to a significant drop of assembly segments (36%).

The major components of Left Front Alliance, which includes Communist Party of India (Marxist), the Congress, a range of smaller communist formations and regional parties from other states, failed to win more a single seat, with the exception of the Bhangore seat, won by a minor partner, the Rashtriya Secular Majlis Party.

The seat of Kalimpong also escaped to the Trinamool Congress and the BJP. It was won by Ruden Sada Lepcha, an independent candidate. It is the first time since Independence that the West Bengal assembly does not have a single communist legislator.

Steady participation

Participation in West Bengal election has been high since the early 1980s, after the communists rose to power. The more competitive the election, the higher the turnout, as we see participation going above 80% around the time the Trinamool emerges as a challenger to the Left.

This year, at 82%, participation remains high and is fairly well distributed across the state. It is the lowest in the hilly parts of the Darjeeling, Kalimpong and Jalpaiguri districts, as well as in parts of the Murshidabad district, a former Congress bastion.

One might have expected participation to dip in the last three-four phases, as the number of Covid-19 cases started surging. We do not observe that. The lower participation in the last two phases can be attributed to the fact that Kolkata usually sees a lower turnout than the rest of the state. In 2021, the Kolkata Corporation area registered 60.1% turnout, against 64.6% in 2016.

Women outvoted men in West Bengal for the first time in 2011. We do not have yet data on the current election but expect the gap between men and women voting rate to slightly increase in favour of women, based on anecdotal evidence and reports from the field.

Higher participation of women however does not mean that more women vote compared to men, since there are fewer women in the electorate, comparatively (because of the skewed sex ratio and a remaining registration gap).

Despite Trinamool’s domination, a growing pool of candidates

The election saw the participation of 2,408 candidates. Of these, 1,254 were on national- and state-based party tickets, 251 on local party tickets and 611 were independents. Only 38% (1,498) saved their deposit. As West Bengal’s political scene gets more and more dominated by the Trinamool Congress, we see more and more candidates contesting.

Sixty parties entered the fray, also the highest number ever. Only three of them however have obtained representation, due to the sweeping performance of the Trinamool Congress and the good showing of the BJP. With the Left and the Congress out, this is the least diverse assembly in the history of Bengal, as far as party representation is concerned.

Geography of the results

The BJP has its first break in West Bengal in the 2019 General Election, when it swept distinct sub-regions in West Bengal. It won nearly all the seats in the Jalpaiguri division in the North, the Medinipur division in the South-West, the Burdwan Division’s districts that border Bihar and a cluster of seats in the North of the Presidency Division. It was also competitive in the Malda Division, around the area called the “Chicken Neck”.

Border districts in West Bengal host a larger non-Bengali speaking population, both tribal or hailing from neighbouring states. They also have a larger Scheduled Caste population compared to the districts surrounding Kolkata.

In 2021, the BJP continues to perform well in the North, but loses quite a lot of ground in those border and Southern districts. The Trinamool on the other hand expands significantly in the Malda and Murshidabad region, the last Congress bastions in the state.

A comparison of the 2021 and 2016 maps show that even though the Trinamool Congress improved its tally in the assembly, the geography of its victory is not as widespread as it was five years before. In 2016, the Trinamool swept across all divisions or sub-regions, including the Northern districts. Only the Malda and parts of the Murshidabad regions kept supporting the Left and the Congress

In comparison with the 2016 election, the geography of the party performance in 2021 reveals the constitution of clusters where the BJP maintains a strong presence.

The continuous rise of the Trinamool

It is rare for a party in India to win more than two consecutive terms. It is even rarer to do this with increasing vote share, as the next chart illustrates. Since 2006, the Trinamool Congress steadfastly increased its vote share, which is unusual as incumbent chief ministers often see their popularity being eroded over time. One can also measure the amplitude of the rise of the BJP, which gains 26% of vote share compared to 2016.

Not all parties contest every seat, specifically the Left Secular Alliance.

The following chart shows how the Communist Party of India (Marxist), within its alliance, used to score massive vote shares in the seats it contested. Until 2006, its candidates would on average score 50% vote share. Even in 2011 and 2016, when it lost to the Trinamool Congress, its candidates remained quite competitive, getting average vote shares of above 40%.

The Congress, on the other hand, suffered from the split with the Trinamool Congress and saw its vote share dip in 2006. But it got back on its feet thereafter and regained strength, although in a smaller number of seats. Just like the Left, its vote share in seats contested also collapsed. This year will be remembered as the election where the Left and the Congress were wiped out from the electoral map.

With 47% of the votes, the Trinamool Congress now holds 73% of the seats. Only the Congress did better in the 1972 election, with 77% of the seats, after Indira Gandhi’s military victory in Bangladesh. The communists at their peak never won more than 64% of all seats in the state.

Since the Congress and the Left have been contesting in an alliance in recent elections, the strike rate can tell us whether their performance within that alliance differed.

The following chart shows that within the alliance, the Congress kept performing quite well, winning 64% of the seats it contested in 2011, and 48% of the seats it contested in 2016. The reason for that is that Congress voters remained concentrated in certain areas, while Communist Party of India (Marxist) votes were more geographically dispersed. In 2021, both parties failed to win a single seat.

Phase-wise vote shares

This was a long election with an unprecedented eight phases. Such a long campaign give opportunities to parties to adjust their campaigns, change their tone and strategies, adapt to circumstances, in the hope of improving their performance over time.

A phase-wise examination of the two main parties vote share reveal that the election was lost by the BJP from the beginning. From the first phase, the Trinamool Congress converted more seats than the BJP and as the campaign unfolded, the gap between the two parties kept increasing. There is a 26% difference of vote share between the two parties in phase 3. That gap even increases to 29% and 30% in the last two phases, an enormous difference.

In 2019, the BJP beat the Trinamool Congress in two of the eight phases (we compare the same assembly segments by phase for both elections). The gap in phase 3 was already wide, as well as in phase 8, which include half of the Kolkata Corporation segments. Phase 3 took place in Howrah district, as well as in South 24 Parganas, both adjacent to Kolkata.

Another way to represent that data is to look at the performance variation between 2019 and 2021, by comparing the same segments by phase. This shows that the Trinamool Congress improved its performance across phases (except the third) and that it made spectacular vote gains in the last two phases, notably in Kolkata, but also in parts of Malda and Uttar Dinajpur.

The Trinamool peaked in the Kolkata Corporation, at 62% of the vote. This is a clean rejection of the BJP in the city already badly affected by Covid-19 at the time of polling, but also the city where we saw civic networks mobilising against the BJP.

The BJP did, however, marginally increase its vote share in Kolkata, but lost ground across phases, compared to 2019. It lost the most in phase 1 and in phase 5, which took place in BJP strongholds.

This indicates the presence of a one-way verdict. The Trinamool defeated the BJP practically everywhere and the outcome is not simply the result of demographic or vote concentration effects.

Close contests: things could have been worse for the BJP

Wherever the Trinamool candidates won, they did so with much higher victory margins than the BJP. Trinamool candidates were also quite competitive in the seats won by the BJP.

An examination of close contests (a victory margin of less than 5,000 votes) shows that the BJP narrowly won in 22 of its 77 seats. A small change of votes in those seats could have drastically reduce its tally, in greater proportion than for the Trinamool, which narrowly won in only 13 seats.

This is also indicative of the decisive character of most individual races. The bulk of the Trinamool victories were actually quite emphatic, across the state.

The BJP narrows the gap in reserved seats

More than half of the seats won by the BJP were reserved seats (32 Scheduled Caste and seven Scheduled Tribe seats). Without survey data, one cannot say whether Scheduled Caste and Scheduled Tribe voters consolidated their support behind the BJP, but it was expected that the BJP would do well in those areas, where it also scored in 2019.

What does this data tell us? First, that the Trinamool’s victory cuts across most of the state’s territory and across the eight phases of the election. From phase 1, the Trinamool took the lead and the gap kept increasing phase after phase thereafter. It reached a single majority of seats by phase 6 and consolidated its victory by sweeping Kolkata.

Winning a third consecutive term with increased performance is a rare feat in Indian politics. Considering that the Trinamool faced an adversary that put everything it had in the balance – money, organisation, nationalist rhetoric, a campaign speech from Bangladesh and the personal involvement of the prime minister who held more than 20 rallies before and during the campaign – the party’s performance is all the more remarkable.

Here is not the place to provide an explanation for this outcome. Data merely help us to dissect the amplitude and features of an electoral outcome, not explain how that outcome was produced in the first place.

Gilles Verniers is Assistant Professor of Political Science at Ashoka University, co-Director of TCPD and Visiting Senior Fellow at the Centre for Policy Research. Basim-U-Nissa is affiliate researcher at TCPD. Mohit Kumar and Neelesh Agrawal are Research Engineers at TCPD.