India, Feb. 14 -- Sweeping victories usually offer little scope for detailed interpretation as all data tends to point in the same direction. The Aam Aadmi Party (AAP)'s performance in this state election was remarkable for many reasons. First, AAP maintained an extremely high vote share as an incumbent, which is rare. Forty of its 43 re-running MLAs won their race, which is even rarer as voters tend to reject usually half of those they elected in the previous election.

The performance is also all the more remarkable when one compares it to its poor showing in the last general election. Barely eight months ago, the AAP scored less than 20% vote share, stood behind Congress and failed to win a single Delhi assembly segment. It now won 62 of...