3 Seat shares might be trickier to predict than vote shares in Gujarat

This is where the vagaries of the first-past-the-post system come into play. If one were to mechanically halve the Congress’s 2017 vote share in every AC, as the CSDS poll shows at the state level, and do similar adjustments for the BJP and the combined vote share of other parties and give the remaining votes to the AAP, the BJP’S seat tally will reach an overwhelming 172 in the 182-member assembly. As is obvious, this is an extremely unlikely outcome, the reason being, vote shares of parties always have a significant variation at the assembly constituency (AC) level. An Ac-wise distribution of the AAP’S debut in assembly elections in Delhi (2013) and Punjab (2017) shows clearly that the headline vote share at the state level was not distributed evenly at the AC level.

This is where AAP’S regional impact in Gujarat will come into play. A comparison of the last two Gujarat assembly election results (ACS of the elections before 2012 aren’t comparable because of delimitation) shows that Gujarat is no exception to the regional dominance of parties. The BJP’S victory margin was 10% (or greater) of the total votes polled in 53 out of the 182 ACS in both 2012 and 2017 elections. But 24 ACS have always seen a tight contest with victory margin of the winning party being less than 5%. As is obvious, the same magnitude of shifting votes (to AAP from the Congress) will have a very different impact on AC level results in this context. Of course, the final vote share figures could turn out to be very different from the CSDS Lokniti projections.

If a significant division of votes does take place between the AAP and the Congress then the BJP might end up improving its seat tally significantly as the vote share threshold required for winning an AC will come down. The best way to understand this argument is to look at the BJP’S seat-share-to-vote-share ratio – it is a useful metric to measure a party’s ability to convert votes into seats in an FPTP system – in past elections in Gujarat. This number was at its lowest since 1995 (the first time the BJP captured power in Gujarat) in the 2017 elections, which was the closest Gujarat has been to a completely bipolar contest.