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Arizona · 2026 forecast · Updated Oct 16, 2026

Who will control the Arizona State Senate?

All 30 seats are on the ballot. 16 seats make a majority. 20 make the two-thirds supermajority that can override a veto.

It's a toss-up: each party wins about half of the simulations.

Democrats
49%
chance of control
Republicans
51%
Avg. D seats
15.580% range 13–18
Avg. R seats
14.580% range 12–17
Now
13 D · 17 R30 up this year

Chance Democrats win a two-thirds supermajority (20+ seats): 1%

13 D nowMarks: two-thirds supermajority for each party17 R now

Democrats are favored to control the Arizona State Senate (69%), which would flip it from Republican control.

Democrats
69%
chance of control
Republicans
31%
Avg. D seats
16.580% range 14–19
Avg. R seats
13.580% range 11–16
Now
13 D · 17 R30 up this year

Chance Democrats win a two-thirds supermajority (20+ seats): 8%

13 D nowMarks: two-thirds supermajority for each party17 R now

16 for control
16 for control
  • Solid D
  • Likely D
  • Lean D
  • Toss-up
  • Lean R
  • Likely R
  • Solid R

Race ratings

All 30 races, grouped by the leader's chance of winning.

2 seats projected to flip: 2 R→D. 1 more is a toss-up that could change parties (flip risk).

2 seats projected to flip: 2 R→D. 3 more are toss-ups that could change parties (flip risk).

Solid D13

Show 7 more

Likely D0

Lean D2

Toss-up1

Lean R1

Likely R4

Solid R9

Solid D11

Likely D2

Lean D2

Toss-up3

Lean R1

Likely R3

Solid R8

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.

The map

Each district colored by the leader's chance of winning. Hover for details; click for the race.

Arizona

Phoenix

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

Seats to watch

The closest races (Lean or Toss-up, Horizon), and the seats most likely to change parties.

Closest races

LD-2Amelia GallitanoShawnna BolickFlip riskFlip risk50%Rep.60%Dem. LD-4Aaron LiebermanCarine WernerD flipD flip60%Dem.63%Dem. LD-17Edgar SotoChris KingFlip risk62%Rep.56%Dem. LD-13Kristie O'BrienJulie WilloughbyD flipD flip71%Dem.76%Dem.

Most likely to flip

LD-13Kristie O'BrienJulie WilloughbyD flipD flip71%to flip76%to flip LD-4Aaron LiebermanCarine WernerD flipD flip60%to flip63%to flip LD-2Amelia GallitanoShawnna BolickFlip riskFlip risk50%to flip60%to flip LD-17Edgar SotoChris KingFlip risk38%to flip56%to flip LD-14Stephanie WalshMylie Biggs11%to flip12%to flip LD-27Kyle ClaytonKevin Payne10%to flip36%to flip LD-16Elaine AldreteT.J. ShopeFlip risk9%to flip44%to flip LD-29Eric StaffordJanae Shamp7%to flip15%to flip LD-9Kiana SearsBridget Fitzgibbons4%to flip12%to flip LD-23Brian FernandezMichelle Altherr4%to flip14%to flip

How the odds have moved

Chance of winning control, by forecast date.

0%25%50%75%100%AugSepOctNovNov 3Democrats 49%Republicans 51%

Updated nightly. Each day is the current model run on the polls that had ended by then (how).

0%25%50%75%100%AugSepOctNovNov 3Democrats 69%Republicans 31%

Updated nightly. Each day is the current model run on the polls that had ended by then (how).

Every outcome we simulated

Democratic seats across 40,000 simulations. Darker bars: the middle 80%.

16 for D control →D two-thirds →← R two-thirds10121416182022
16 for D control →D two-thirds →← R two-thirds1012141618202224

Every race

30 races, 5 without a contest between the major parties.

30 races
DistrictCandidatesChance of winning (D · R)Avg. marginRatingLeanPolls
LD-1
● Christine Dargon● Mark FinchemINC
<1%>99%
1%99%
R+25.7R+27.1Solid RSolid RR+32—
LD-2Flip riskFlip risk
● Amelia Gallitano● Shawnna BolickINC
50%50%
60%40%
R+0.1D+2.3Toss-upToss-upR+5—
LD-3
● Jeff Fortney● John KavanaghINC
1%99%
4%96%
R+21.9R+18.6Solid RSolid RR+24—
LD-4D flipD flip
● Aaron Lieberman● Carine WernerINC
60%40%
63%37%
D+1.9D+3.2Lean DLean DR+3—
LD-5
● Christine Marsh● No RepublicanAlso: Jason LaForest (I)
No Republican on the ballotNo Republican on the ballot—Solid D (no Republican)Solid D (no Republican)D+38—
LD-6
● Jamescita Peshlakai● Lloyd Johnson
>99%<1%
>99%<1%
D+34.6D+33.0Solid DSolid DD+28—
LD-7
● Mike Montiel● Wendy RogersINC
<1%>99%
1%99%
R+27.2R+25.1Solid RSolid RR+30—
LD-8
● Lauren KubyINC● Bill Loughrige
>99%<1%
99%1%
D+31.2D+29.0Solid DSolid DD+22—
LD-9
● Kiana SearsINC● Bridget Fitzgibbons
96%4%
88%12%
D+13.7D+11.3Solid DLikely DD+4—
LD-10
● Blair Moses● Dave FarnsworthINC
1%99%
7%93%
R+17.9R+14.6Solid RLikely RR+21—
LD-11
● Catherine MirandaINC● Joshua Ayala
>99%<1%
>99%<1%
D+47.0D+48.9Solid DSolid DD+44—
LD-12
● Patty Contreras● No RepublicanAlso: Anthony Ramirez (I)
No Republican on the ballotNo Republican on the ballot—Solid D (no Republican)Solid D (no Republican)D+17—
LD-13D flipD flip
● Kristie O'Brien● Julie Willoughby
71%29%
76%24%
D+3.8D+6.5Lean DLean DEven—
LD-14
● Stephanie Walsh● Mylie Biggs
11%89%
12%88%
R+9.1R+11.3Likely RLikely RR+18—
LD-15
● Jayme Accalia● Jake HoffmanINC
<1%>99%
1%99%
R+24.1R+23.5Solid RSolid RR+30—
LD-16Flip risk
● Elaine Aldrete● T.J. ShopeINC
9%91%
44%56%
R+11.2R+1.3Likely RToss-upR+8—
LD-17Flip risk
● Edgar Soto● Chris King
38%62%
56%44%
R+2.2D+1.4Lean RToss-upR+4—
LD-18
● Priya SundareshanINC● Douglas Everett
>99%<1%
>99%<1%
D+33.5D+30.1Solid DSolid DD+24—
LD-19
● Bob Karp● Gail Griffin
1%99%
4%96%
R+17.2R+18.3Solid RSolid RR+24—
LD-20
● Alma Hernandez● No Republican
Democrat unopposedDemocrat unopposed—Uncontested DUncontested DD+46—
LD-21
● Rosanna GabaldónINC● Esteban Flores
>99%<1%
99%1%
D+32.7D+27.2Solid DSolid DD+21—
LD-22
● Eva DiazINC● No Republican
Democrat unopposedDemocrat unopposed—Uncontested DUncontested DD+25—
LD-23
● Brian FernandezINC● Michelle Altherr
96%4%
86%14%
D+15.6D+10.7Solid DLikely DD+5—
LD-24
● Analise OrtizINC● Frank Steele
>99%<1%
99%1%
D+36.3D+29.2Solid DSolid DD+24—
LD-25
● Laura Huber● Tim DunnINC
<1%>99%
2%98%
R+24.2R+21.4Solid RSolid RR+28—
LD-26
● Flavio BravoINC● Jim Bishop
>99%<1%
>99%<1%
D+38.1D+37.2Solid DSolid DD+32—
LD-27
● Kyle Clayton● Kevin PayneINC
10%90%
36%64%
R+10.7R+3.5Likely RLean RR+11—
LD-28
● Michael Braun● Frank CarrollINC
1%99%
4%96%
R+23.3R+17.8Solid RSolid RR+23—
LD-29
● Eric Stafford● Janae ShampINC
7%93%
15%85%
R+11.0R+10.1Likely RLikely RR+17—
LD-30
● No Democrat● Leo Biasiucci
Republican unopposedRepublican unopposed—Uncontested RUncontested RR+55—

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%).