India, Jan. 12 -- Tamil Nadu has been an outlier in Indian politics in some ways. Two aspects of state politics that make it unique are particularly significant. One, no national party has formed a government in the state in close to 60 years: The DMK and its rival, the AIADMK, have won all elections since 1967, either on their own or in alliance. Two, despite alliances becoming essential to winning elections in the state, Tamil Nadu has not seen a coalition government, with the Dravidian majors refusing to share office with their allies. Even in 2006, when the DMK emerged as the single largest party in the assembly but failed to garner a simple majority, M Karunanidhi formed a single-party government. Ahead of the assembly elections, due...