15. Oupalam

All India Anna Dravida Munnetra Kazhagam held the seat; the winning margin narrowed from 19.4% to 14.3%.

Boundaries were redrawn between 2006 and 2011 — the comparison is matched by name and is indicative only.

• Won on a lower shareIts own vote share fell 15.5% — it held because the rest of the vote was more divided.
• New challengerIndependent (IND) finished second with 28.3% — it polled just 0.8% in 2006.
• Vote fragmentedThe top two took only 70.9% between them, down from 96.8% — the field split more ways.

Written from the constituency figures by a fixed set of rules — no language model.