90. Vaikom

Communist Party of India held the seat; the winning margin narrowed from 18.2% to 0.8%.

• Won on a lower shareIts own vote share fell 13.4% — it held because the rest of the vote was more divided.
• New challengerIndependent (IND) finished second with 40.7% — it did not contest here in 1967.
• Vote fragmentedThe top two took only 82.2% between them, down from 91.5% — the field split more ways.

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