Electoral Mechanics Simulator

Stronghold vs Nationwide Electoral Efficiency Model

Model Controls

● LIVE MODEL
High = concentrated in coastal/post-industrial heartlands; Low = uniform national spread.
Average plurality required to win contested constituency seats.
The Stronghold Dilemma: High concentration preserves individual heartlands (e.g. Clacton) with massive surplus votes, but leaves 98% of seats just below plurality thresholds.

Constituency Grid Cartogram (650 Represented Units)

Seat Won
Clacton (Beacon)
Seat Lost

Seat Conversion vs National Vote Share Curve

Current: 18.5% → 5 Seats

Electoral Metrics

Projected Seats 5 0.8% of Parliament
Efficiency Index 0.28 Sub-parity ratio
Wasted Surplus 42.4% Votes in safe seats
Near-Miss Seats 23 Within 5% of threshold

Key Regional Basins

Constituency Sample Type Share Status
FPTP Conversion Law: A uniform 20% vote yields near-zero seats. Under winner-take-all, seat translation stays flat until the national average clears local plurality thresholds (~32-35%), triggering an exponential surge.
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