2009–10 Tamil Nadu Legislative Assembly by-elections

The 2009–10 Tamil Nadu Legislative Assembly by-elections were a series of electoral contests held in the Indian state of Tamil Nadu to fill vacant assembly seats. These by-elections occurred in the context of a political landscape marked by significant party dynamics and regional issues. Held primarily between December 2009 and January 2010, the by-elections were necessitated by the resignation or disqualification of sitting legislators, leading to contests in several constituencies. Major political parties, including the Dravida Munnetra Kazhagam (DMK), the All India Anna Dravida Munnetra Kazhagam (AIADMK), and the Indian Congress, actively engaged in campaigning. The by-elections served as a barometer for public sentiment ahead of the 2011 Tamil Nadu Assembly elections, reflecting shifting alliances and voter preferences within the state.