New Delhi, Feb. 6 -- Exit polls after Assembly elections were held in Delhi on Wednesday show the Bharatiya Janata Party (BJP) winning power. To be sure, such polls have been way off the mark in recent times and sampling errors in India are common. So it's important to wait for results of the vote count.

Yet, should the forecasts turn out right, the BJP would oust the Aam Aadmi Party (AAP), whose decade-long hold on Delhi had defied its political sway across India. It would mark its return to power in Delhi after more than two-and-a-half decades, since AAP had taken it from the Congress, which also had a long stint running this Union territory with state-like characteristics.

The swing in votes away from AAP would have to be large for i...