A 435-seat chamber. Adjust the seven knobs and watch the median
representative's ideology distribution change. Values are in
percentage points. Each simulation = 1000 election runs.
·
Compare against historical House results, 1992–2024 →
Election Environment
Drag right for a Republican wave, left for a Democratic
wave.
District Map
Share of districts that are packed safe-D seats. Slide
right to gerrymander more aggressively in Democrats'
favour.
Share of districts that are packed safe-R seats. Slide
right to gerrymander more aggressively in Republicans'
favour.
Candidates
Higher → Democrats run more moderate candidates across
all districts.
Higher → Republicans run more moderate candidates
across all districts.
Higher → Democrats run more moderate candidates in
swing districts.
Higher → Republicans run more moderate candidates in
swing districts.
Higher → Democrats run more moderate candidates in red
districts.
Higher → Republicans run more moderate candidates in
blue districts.
Voters
Higher → voters punish ideologically extreme candidates
more heavily, relative to how partisan the district
is.
Lower → election outcomes track district partisan lean
and candidate ideology more deterministically. Higher →
more random per-district swings.
Running…
Cell colour = party of victory + margin of victory.
1st: histogram of the median representative's ideology
across 1000 simulations, colored by party (blue = Democrat,
red = Republican).
2nd: one example chamber — each district's partisan lean vs
the elected representative's ideology. The black star marks
the median rep.
3rd: histogram of district partisan lean across the chamber.
Each district is one cell stacked in its partisan lean bin;
cell colour = party of victory + margin of victory —
blue if the simulator's D candidate is expected to win,
red if the R is, with darker shades for larger predicted
margins.
4th: distribution of final Republican seats across the 1000
simulations. Bars are red when R holds a majority and blue
when D does, split at the chamber's majority threshold.
See more plots
20 example chambers + mismatch distribution
under the current sliders.