Tamilaga Vettri Kazhagam has broken Tamil Nadu’s bipolar political structure for the first time since 1977, with electoral data revealing a direct erosion of All India Anna Dravida Munnetra Kazhagam core voter support. Analysis of 134 direct contests among TVK, DMK and AIADMK shows AIADMK’s vote share hitting record lows in three of five regions, while DMK largely held its base.

Region-wise vote share comparisons indicate AIADMK recorded its weakest performance in 2026 across Greater Chennai, central and south regions. DMK’s lowest vote share was confined to Greater Chennai, with stronger retention in central, north and west regions. A robust negative correlation between AIADMK and TVK vote shares across most constituencies confirms a transfer of core voters from the former to the latter.

Data on vote share changes since 2021 show DMK lost 13.9 percentage points overall against AIADMK’s 12.0-point drop across these seats. Analysts note DMK losses were driven by swing voters shifting to TVK, while AIADMK losses reflect a smaller but deeper contraction in its structural support base. This pattern threatens AIADMK’s political identity as the principal anti-DMK pole.

AIADMK now faces a structural challenge in consolidating its base against TVK inroads, even as anti-incumbency flows were insufficient to push DMK below AIADMK. Party strategists are recalibrating outreach to prevent further core voter attrition ahead of upcoming electoral cycles.