Bhatnagar International School in Vasant Kunj had four polling booths (34, 35, 36 and 38) for the Mehrauli assembly constituency (AC) in Delhi. The Aam Aadmi Party (AAP) won from each of these booths in the recently concluded assembly elections. However, the winning margins were very different. The AAP had a lead of 1.2, 10.4, 24.1 and 52.8 percentage points over the Bharatiya Janata Party (BJP) in terms of vote share from booth numbers 35, 34, 36 and 38 respectively.

What explains this drastic difference in support levels in such close proximity?

A Hindustan Times analysis of booth-wise votes suggests that the answer could be the class background of voters. Booth number 38, where AAP had the biggest lead, has voters from only Bandhu Camp, a slum cluster in what is otherwise an upper middle-class locality. Booth number 35, where AAP’s victory margin is the smallest comprises 272 DDA flats in Vasant Kunj. This micro level data point gives a clear idea about how the AAP got re-elected with such a big majority.

Sure, it had support from all sections of Delhi’s population, but it is the city-state’s poorest voters, who gave it the biggest lead vis-à-vis the BJP.

The analysis is based on results from all of Delhi’s 13,747 polling booths correlated with the localities these booths serve. The booths have been classified into different kinds of localities such as authorized, planned and unauthorized colonies by Shamindra Nath Roy, a senior researcher at the Centre for Policy Research, and Anirvan Chowdhury, a PhD candidate at the University of California, Berkeley. This classification is based on the most prominent form of settlement in the locality.

At least 50% of Delhi’s booths fall in rural or urban villages, unauthorized colonies, resettlement colonies and slum clusters. About one-third are located in planned and regularized localities, which are most likely to have well-off voters. The remaining localities have mixed settlements or are part of Delhi’s old settlements. To be sure, because the classification is based on the most prevailing settlement that a booth caters to, it does not account for small slums or colonies inside the localities that may be of a different kind. For example, the Bandhu Camp named above is only a small part of Vasant Kunj locality, so its booth has been classified as planned, rather than as a slum cluster.

With this caveat in place, an analysis of booth-level data using this dataset shows that the AAP performed the best in terms of both vote share and the share of booths won in slum clusters and resettlement colonies.

The party won 97% and 90% of the booths in these respectively. But this does not play a significant role in the party’s overall performance because only about 6% booths fall in these localities. On the other hand, the party’s lead in unauthorized colonies, villages and mixed localities played a significant role in its overall performance. It had a lead in more than 60% booths in these types of localities. These localities comprise about 54% of the booths in Delhi.

The party’s performance was relatively poor in planned and regularised colonies even though it managed a lead in a majority of booths there as well.

Even within the planned and regularised colonies, anecdotal evidence suggests that BJP’s support increases with opulence levels. For example, the AAP had a lead of only 3.2 and 3.7 percentage points in booth number 112 and 113 of the R K Puram AC, which has voters from D-Block (Vasant Vihar) and E-Block, Poorvi Marg (Vasant Vihar), among the most posh areas in Delhi. This difference increases to 25.7 and 34.7 percentage points for booth numbers 27 and 80, which have voters from Sector 10 and Sector 1 of R K Puram, who are most likely to be government employees. In R K Puram’s booth number 49, which has voters from only Sonia Gandhi camp, a jhuggi-jhopri in Sector 7 (R K Puram), the AAP got 58.8% votes, nearly 35 percentage points more than the BJP, while the Congress got just 3% votes.

To be sure, the AAP could not have managed to win Delhi with the support of the poorer sections of the society alone. Unauthorized colonies, villages and slum clusters account for at least 50% booths in only 30 ACs and AAP won 27 of them. There are also 17 ACs where these types of settlements account for less than 10% booths and AAP won 15 of them.

This is not to say that class alone can explain the Delhi results. For example, the AAP won every single booth in unauthorized colonies in seven ACs, while it won less than 30% booths in such colonies in 10 other ACs. Similarly, it won all booths in regularized colonies in seven ACs and less than 30% booths in regularized colonies in six other ACs. This is because voting trends tend to vary within the same class group with other factors such as socio-religious demographic composition and local developmental issues.