The Mettur constituency could be taken as a one of the samples of whether the implementation of 10.5% of internal reservation for the Vanniyar community has worked in favour of the ruling combine.
Vanniyars form the major vote base in the constituency which includes the Mettur dam that meets the water needs of a major parts of Tamil Nadu. The constituency has elected candidates of all the major parties in the past elections.
Major industries like Chemplast, besides Mettur thermal power plant are located in the constituency making it an important industrial hub of the district.
Agriculture is another major industry in the region. Farmers in the region have been demanding better measures for irrigation of farm lands.
The implementation of ₹565-crore Mettur surplus water scheme, one of the long-standing demands of farmers in the region to lift surplus water from the Mettur dam to fill dry lakes in the region has obviously rejoiced the farmers. A total of 100 dry lakes in four constituencies, Mettur, Omalur, Sankagiri and Edappadi would benefit under the scheme.
Despite a major industrial region, public in the region have been demanding better, expanded roads. They have also been demanding measures to improve tourism in and around the dam and development of the dam park.
Tomato is a major crop harvested in the region and farmers have been demanding measures for better price and production of value-added products.
The incumbent AIADMK legislator S.Semmalai is not contesting the elections this time and the ruling alliance has allotted the seat to PMK. S. Sadhasivam, State vice-president of the party is contesting from the constituency. The Makkal Needhi Maiam has fielded a young woman candidate P. Anusya. S. Srinivasa Perumal is contesting in DMK ticket and Ramesh Aravind is the DMDK nominee in the constituency.
In the 2011 elections, S.R. Parthiban, the present Salem MP won from the constituency in DMDK ticket with a margin of 2,594 votes.
In the 2016 Assembly election here, Semmalai. S won the elections in AIADMK ticket with a margin of 6,282 votes.