Door-to-Door GOTV Canvassing — New Haven

Summary

The New Haven canvassing experiment established one of the most durable findings in political science: personal contact substantially increases voter turnout, while impersonal contact (mail, phone) has little effect. The mechanism is human social connection — canvassers are neighbors and community members, not call-center operators. The size of the effect (5–9 pp) is large relative to most civic interventions and has been replicated across party contexts, candidate types, and countries. The experiment also established a key null: direct mail, despite its ubiquity in political campaigns, has no reliable effect on turnout. Money spent on mail could produce 6x more turnout if spent on canvassers.

Research question

"Does in-person door-to-door canvassing increase voter turnout compared to direct mail or phone contact?"

Methodology

Result

Positive

Personal canvassing: +6 to +9 pp; direct mail: +0 to +1 pp (not significant); phone calls: +3 pp. Effect of canvassing has been replicated in 50+ subsequent studies with consistent range of 5–10 pp.

Evidence strength

Strong

Randomized trial, replicated across multiple sites or studies.

Replication status

Replicated