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Missouri · 2026 forecast · Midwest region · Updated Oct 16, 2026

Missouri in 2026

Missouri elects an auditor, all 8 members of the U.S. House, 17 of 34 members of the State Senate and all 163 members of the House of Representatives on November 3, 2026.

On the November 3 ballot: 1 statewide office · 8 U.S. House seats · 2 legislative chambers.

U.S. House
2.4 D · 5.6 R2.5 D · 5.5 RExpected seats of 8 · 1 toss-up
Missouri State Senate
R >99%R >99%Chance of control · 17 of 34 seats up
Missouri House of Representatives
R >99%R >99%Chance of control · 163 of 163 seats up
Auditor
R 89%R 71%Quentin Wilson vs. Scott Fitzpatrick

U.S. House districts · Missouri

  • Solid D
  • Likely D
  • Lean D
  • Toss-up
  • Lean R
  • Likely R
  • Solid R
  • Projected flip (stripes: party holding it now)

Trifecta

Republican trifecta now

Republicans hold the governorship and every legislative chamber. A trifecta is one party holding all of them.

After the election

Dem. trifecta
<1%
Divided
<1%
Rep. trifecta
>99%

The Republican trifecta most likely continues (>99%); <1% chance it is broken.

After the election

Dem. trifecta
<1%
Divided
<1%
Rep. trifecta
>99%

The Republican trifecta most likely continues (>99%); <1% chance it is broken.

Chances come from the same simulations as the races, so outcomes are correlated. A governorship or chamber not on the ballot this year keeps its current party. Source: 99chambers forecast, run 56, updated Oct 16, 2026.

Statewide races

Every race decided by the whole state. Statewide offices nationwide.

Statewide offices

Auditor

Likely RLean R
● Quentin Wilson● Scott FitzpatrickINC
11%89%
29%71%

The Missouri environment

The environment Missouri's governor, statewide and legislative races run in, read from their polls against what the fundamentals expect. Its federal races run in the national environment.

National environment
D+9.5Election Day forecast, national House vote
Missouri state offices vs. the nation
+0.6± 4.3 (80% range) · 1 polled state race
Missouri state-office environment
D+10.10.6 pts more Democratic than the nation

The polled state races behind it

← Runs more RepublicanRuns more Democratic →Missouri estimateWeighted, pulled toward the nationMissouri AuditorPolls R+1.1 · 8% of the estimate

Over time

EvenD+5D+10Oct 10Oct 16Missouri D+10.1Nation D+9.5

Each polled race's average, minus what the fundamentals expect at the national environment, in national-environment points (a dot right of center runs more Democratic than expected). Readings are weighted by poll precision and office (governor most, then other statewide races, the Senate, legislative and House races), centered on the national average and pulled toward zero, so a thinly polled state stays near the nation. Governor, statewide and legislative races use the Missouri environment in full; Senate and House races 0% of it. Each race's own polls are left out of the environment it uses.

U.S. House

8 districts. The national House forecast.

Solid D2

Likely D0

Lean D0

Toss-up1

Lean R0

Likely R0

Solid R5

Solid D2

Likely D0

Lean D0

Toss-up1

Lean R0

Likely R0

Solid R5

Columns follow the chance of winning: Toss-up 40–60%, Lean 60–80%, Likely 80–95%, Solid 95%+. The square shows who holds the seat now (■ Democrats, ■ Republicans). risk: a toss-up (40–60%) that could change parties.

St. Louis

8 races
DistrictCandidatesChance of winning (D · R)Avg. marginRatingLeanPolls
MO-1
● Wesley BellINC● Paul Berry
>99%<1%
>99%<1%
D+66.0D+65.2Solid DSolid DD+59—
MO-2Flip riskFlip risk
● Fred Wellman● Ann WagnerINC
43%57%
49%51%
R+1.1R+0.2Toss-upToss-upR+8—
MO-3
● Bethany Mann● Bob OnderINC
1%99%
2%98%
R+19.0R+19.3Solid RSolid RR+27—
MO-4
● Jordan Herrera● Mark AlfordINC
<1%>99%
<1%>99%
R+34.4R+35.2Solid RSolid RR+42—
MO-5
● Emanuel CleaverINC● Rick Brattin
>99%<1%
>99%<1%
D+33.0D+32.5Solid DSolid DD+24—
MO-6
● Josh Smead● Chris Stigall
<1%>99%
<1%>99%
R+28.2R+31.6Solid RSolid RR+39—
MO-7
● Missi Hesketh● Eric BurlisonINC
<1%>99%
<1%>99%
R+33.4R+35.4Solid RSolid RR+43—
MO-8
● Chris Reichard● Jason SmithINC
<1%>99%
<1%>99%
R+44.9R+47.3Solid RSolid RR+54—

Lean: how much more Democratic (D+) or Republican (R+) the place voted for president than the nation (2024 weighted 75%, 2020 25%). Ratings follow the chance of winning: Toss-up 40–60%, Lean 60–80%, Likely 80–95%, Solid 95%+. INC = incumbent running. D flip / R flip: another party is favored (60% or more) over the party holding the seat now (hover for the chance it changes parties); Flip risk: the seat is a toss-up (40–60%).

Missouri General Assembly

Chance of control after November 3, and how each chamber's races rate.

Missouri State Senate

Dem.
<1%
Rep.
>99%

Avg. 12 D – 22 R seats · 18 for control · R supermajority now: 36% it holds

Dem.
<1%
Rep.
>99%

Avg. 12 D – 23 R seats · 18 for control · R supermajority now: 48% it holds

17 of 34 seats up; 17 holdovers.

Full forecast

Missouri State Senate ratings

2 seats projected to flip: 2 R→D.

1 seat projected to flip: 1 R→D. 1 more is a toss-up that could change parties (flip risk).

Solid D3

Likely D0

Lean D2

Toss-up0

Lean R1

Likely R0

Solid R11

Solid D3

Likely D0

Lean D1

Toss-up1

Lean R1

Likely R0

Solid R11

Columns follow the chance of winning: Toss-up 40–60%, Lean 60–80%, Likely 80–95%, Solid 95%+. The square shows who holds the seat now (■ Democrats, ■ Republicans). flip: projected to change parties, in the color of the party favored to gain it. risk: a toss-up (40–60%) that could change parties. Underlined: two candidates of one party in November. Faded: no major-party opponent. Every race.

Missouri House of Representatives

Dem.
<1%
Rep.
>99%

Avg. 64 D – 99 R seats · 82 for control · R two-thirds supermajority 4%

Dem.
<1%
Rep.
>99%

Avg. 63 D – 101 R seats · 82 for control · R two-thirds supermajority 7%

Full forecast

Missouri House of Representatives ratings

10 seats projected to flip: 10 R→D. 4 more are toss-ups that could change parties (flip risk).

11 seats projected to flip: 11 R→D. 4 more are toss-ups that could change parties (flip risk).

Solid D50

Likely D6

Lean D6

Toss-up4

Lean R4

Likely R7

Solid R86

Solid D42

Likely D13

Lean D7

Toss-up4

Lean R3

Likely R12

Solid R82

Columns follow the chance of winning: Toss-up 40–60%, Lean 60–80%, Likely 80–95%, Solid 95%+. The square shows who holds the seat now (■ Democrats, ■ Republicans). flip: projected to change parties, in the color of the party favored to gain it. risk: a toss-up (40–60%) that could change parties. Faded: no major-party opponent. Every race.

Closest legislative races

HD-104Tara MurrayTerri VioletFlip riskFlip risk51%Rep.53%Dem. HD-89Bryan TroopGeorge HruzaFlip riskD flip56%Dem.64%Dem. HD-31Justin GeiserRon FowlerFlip riskFlip risk58%Rep.55%Rep. HD-106Jewel KellyTravis WilsonFlip riskD flip59%Dem.64%Dem. HD-94Cathy A SummersMaryellen MurphyD flipFlip risk64%Dem.51%Dem. HD-56Staci CzarSteve Baker67%Rep.82%Rep.
HD-16Dan KinateChris BrownD flipD flip69%Dem.75%Dem. SD-8Keri IngleJonathan PattersonD flipFlip risk70%Dem.55%Dem. SD-34Shereka BarnesMike Jones71%Rep.69%Rep. HD-10LaTonya T. WilliamsPaul Gatewood73%Rep.77%Rep. HD-60Suzanne LutherShane Kampeter76%Rep.78%Rep. SD-30Betsy FogleMelanie StinnettD flipD flip76%Dem.65%Dem.

How Missouri votes

Election rules that differ from the usual party primary and plurality win.

Staggered Senate

Senators serve four-year terms; half the seats are on the ballot each election.

17 of 34 seats on the ballot; 17 holdovers (7 D, 10 R) serve until a later election.