84. Idukki

Indian National Congress held the seat; the winning margin narrowed from 7.2% to 1.7%.

• Won on a lower shareIts own vote share fell 15.6% — it held because the rest of the vote was more divided.
• New challengerIndependent (IND) finished second with 34.7% — it polled just 1.5% in 1982.
• Vote fragmentedThe top two took only 71.1% between them, down from 96.9% — the field split more ways.

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