Races · house · 2026 · Illinois

house · open seat

Bill Foster vs Jeff Walter

← Illinois house Illinois house →

Safe DD +19.9 forecast · 3 months 27 days to election· 0 polls · 2 marketsMarkets 11h agoRating today

Live model · win probabilityupdated 11h ago · poliagg-v34
94% Foster (D)
6% Walter (R)
Win probability
Bill Foster94% (D)
Jeff Walter6% (R)
Modelupdated 11h ago · poliagg-v34
Chance of winning across many simulations of the race — not projected vote share.
R+15R+5TIEDD+5D+15
Predicted margin
Point estimateD +19.9
80% CID+3.8 → D+36.0
The model’s central margin (D-positive) with its 80% interval — the shaded band on the scale.
Predicted final margin D +19.9 · 80% CI D+3.8 → D+36.0 · 3 months 27 days to election

Momentum

—

insufficient data

Tipping-point P

3.8%

Decisive for chamber control

Market · D-side

D 93¢

Cross-platform consensus

News articles · 30d

articles · new

Caution · early warning

Editorial raters moved while polling has gone quiet

The last rating change here was 22d ago, but only 0 polls have landed in the last 60 days. When raters move and pollsters don't, the rating shift may be running ahead of the data. Watch for a late-cycle correction in either direction.

Where this race stands

Verified

Lean D · model 94% D

No recent polls or markets for this race. PVI baseline (D+6) suggests Lean D.

The poliagg-v34 ensemble forecasts D+19.9 with an 80% CI ranging from D+3.8 (10th pctile) to D+36.0 (90th pctile), giving D a 94% chance of winning.

Tipping-point probability: 3.8% of simulations see this race as decisive for chamber control.

CITATIONS · lean-d · low-tipping

Forecast · poliagg-v34

Predicted final margin

D +19.9

80% CI: D +3.8 → D +36.0 · win prob 94%

R+45R+23TIEDD+23D+45

Quality · inputs

Data quality · medium

Polls used	0
Days to election	118
Residual σ	12.56pt
Generated	7/7/2026

▼ Compare with other models2 models

qgbt-v1GBT (qgbt)

D +12.6

80% CI D +7.8 → D +23.0

CV MAE 8.51

consensusMarket-implied

D +14.0

no interval

market-implied

Prediction markets

Consensus · D 93¢1 platformupdated 11h ago

Cross-platform price · history

85¢90¢95¢100¢54 DAYS · D YES PRICENOWMay 14Jul 7

Per-platform · current

Platform	D YES	R YES	7d Δ	Vol	vs cons
Polymarket “Will the Republican Party win the IL-11 House seat?”	93¢	8¢	+0¢	—	+0

Endorsements · 9 total

Source · Wikipedia · 0 candidates with no endorsements yet

7Foster · 78%
Walter · 22%2
Endorsements tracked
Bill Foster7 · 78%
Jeff Walter2 · 22%
Total9
Scraped from each candidate’s Wikipedia endorsement list.

DBill Foster7 endorsers

Most notable · AFL-CIO · s AFL-CIO

Organizations7

RJeff Walter2 endorsers

Most notable · Chicago Tribune

Newspapers2

Money raised · own committees

FEC Schedule E (independent expenditures) + candidate-committee totals · last filing —

Bill FosterOWN COMMITTEE

Receipts

$1.8M

Disburse

$1.0M

Cash on hand

$2.3M

Debts

$1.0M

Top industries

No industry data.

Top contributors

No contributor data.

Jeff WalterOWN COMMITTEE

Receipts

$186.3K

Disburse

$177.2K

Cash on hand

$9.1K

Debts

$124.6K

Top industries

No industry data.

Top contributors

No contributor data.

Editorial ratings · 4 raters

Cook · Sabato · Inside Elections · 538 · DDHQ et al.

Safe D4

Cook Political Report

Safe D

Jun 17

Inside Elections

Safe D

Jun 24

Sabato's Crystal Ball

Safe D

Jun 8

Split Ticket

Safe D

Jun 24

Demographic crosstabs

age · education · race · gender

No demographic crosstabs published for this race yet. Most pollsters release only topline numbers; subgroup breakdowns (age, education, race, gender) appear here when a pollster publishes them.