Try a different seat total and see what it would mean. Your choices are hypothetical; the published forecast stays unchanged.
Democrats end the Republican supermajority with 55 of 163 House seats or 12 of 34 Senate seats. Ending that supermajority in either chamber means a veto override would need Democratic votes. It is a different question from control of the legislature.
What would end the Republican supermajority?
Published forecast 89.3% chance Democrats end the Republican supermajority
Republicans need 109 of 163 seats for a supermajority: two-thirds of the chamber. Democrats need 55 seats to end it.
60 D Democratic103 R Republican
Each square is one seat. These are generic totals, not a prediction of which districts change hands.
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Hypothetical: Republican supermajority ended
Exactly 60 Democratic seats appeared in 8.3% of the simulations. At least 60 appeared in 53.0%.
How often did each total happen?
Height shows the share of simulated outcomes. Amber marks your selected total. A total absent from the samples is not impossible.
Most frequent total: 8.5% of samples
39 D seats126 D seats
Select a bar to try that total. Scroll through totals or use the selector above.
Forecast of Nov 3, 12:24 pm CT. 100,000 simulations, including shared uncertainty across races. Selecting a total does not rerun the model. Method · Source data.
What a supermajority changes
Veto overrides. Overriding a governor’s veto requires two-thirds of each chamber (Missouri Constitution, Article III, Section 32). If Democrats end the Republican supermajority in either chamber, Republicans would need Democratic votes.
Emergency clauses. Making a bill effective immediately rather than 90 days after the session requires a two-thirds vote (Article III, Section 29).
Control is a separate question. Republicans are favored to keep their legislative majorities; this tool explores the higher two-thirds threshold.
Half the Senate is not on the ballot. Only 17 even-numbered districts vote this year. The other 17 seats are holdovers, included in every scenario and marked with hatching.