When IVRS still beats every newer channel
Feature-phone reach is the honest answer. In semi-urban and rural belts across Karnataka, Bihar, Odisha and MP, 30–45% of the electoral roll still uses a phone that cannot install anything. For that segment, IVRS reaches more voters at lower cost than SMS (which they cannot read), WhatsApp (which they do not have) or AI voice (which is expensive if you only need a press-1 answer).
How a press-key poll is designed
Two to four questions, single-select, in that order: issue salience first ("press 1 if water is your biggest concern, press 2 for roads, press 3 for jobs"), candidate awareness second, vote intention third if the campaign is late enough that people will tell you. Anything more than four questions and drop-off past question two crosses 70%. The recording is fifteen seconds of setup, five seconds per question, and one line of thanks — thirty-five seconds end to end.
Missed-call variant and warm-lead capture
A missed call to a published number triggers an outbound IVRS call within ninety seconds. This is how a hoarding, a poster or a rally banner becomes an interactive channel — the voter dials in for free, hears the survey, and the campaign has a phone number tagged to source, ward and hour. In one Karnataka assembly seat this generated 41,000 warm contacts in eleven days at ₹0.60 per contact.
Rolling tracker, not a one-shot poll
The value of IVRS is not the single-shot answer, it is the rolling three-day tracker on a rotating sample of 3,000–5,000 numbers. When issue-one salience drops six points in a week, you catch it before the opposition does. When candidate awareness plateaus in a specific booth cluster, the ground team is dispatched there on Monday.