Horizon · our Election Day forecast: polls, plus fundamentals like incumbency, fundraising and past results.

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Illinois › U.S. Senate · November 3, 2026 · Updated Oct 16, 2026

U.S. Senate in Illinois

Stratton is very likely to win: Stratton wins in 49 of every 50 simulations.

Stratton (D)
98%
chance of winning
Tracy (R)
2%
Average margin
D+17.1
80% of outcomes
D+8 to D+27
Partisan lean
D+13
Polls
1in our database

Stratton is very likely to win: Stratton wins in 49 of every 50 simulations.

Stratton (D)
97%
chance of winning
Tracy (R)
3%
Average margin
D+16.8
80% of outcomes
D+6 to D+28
Partisan lean
D+13
Polls
1in our database

Range of outcomes

D+17.1R+40R+20EvenD+20D+40
D+16.8R+40R+20EvenD+20D+40

How the odds have moved

Chance of winning by forecast date.

0%25%50%75%100%AugSepOctNovNov 3Stratton 98%Tracy 2%

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

0%25%50%75%100%AugSepOctNovNov 3Stratton 97%Tracy 3%

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

The candidates

Democratic

Juliana Stratton

Lieutenant governor of Illinois (2019–present)

Experience
Statewide office or Congress
Raised
$5.9M
From individuals
$4.9M
Spent
$4.8M
Cash on hand
$1.1M

Money: FEC, through Jun 30, 2026.

Profile and career · Wikipedia

Republican

Don Tracy

Former chair of the Illinois Republican Party (2021–2024), former member of the Illinois Gaming Board (2015–2019), candidate for lieutenant governor in 2010, and brother-in-law of state Senator Jil Tracy

Experience
No elected office
Raised
$4.1M
From individuals
$570.9K
Spent
$3M
Cash on hand
$1.1M

Money: FEC, through Sep 30, 2026.

Profile and career · Wikipedia

What goes into the forecast

Every ingredient's estimate of the final margin.

National environment
D+9.5Election Day forecast; federal races run in it
← RepublicanDemocratic →Lean + environmentUsual vote, shifted by the national and state moodD+21.9Fundamentals modelAdds incumbency, past results, money andexperienceD+23.1Polls in similar placesPolling of similar races in Illinois andlook-alike placesD+23.9Polling average1 poll, latest Oct 1D+11.6Horizon forecastPolls + fundamentals, projected to Election DayD+17.2Pulse forecastPolls (and polling of similar places) only, todayD+16.8

Each estimate is a margin before national and statewide uncertainty is simulated. Horizon blends polls, fundamentals and a little of the similar-places estimate, weighting each by how precise it is; Pulse uses polls and similar places only.

Fundamentals inputs
Incumbency (+1 D, −1 R)0
Fundraising edge (log ratio of individual money)1.89
Elected-experience edge1
First-term incumbent0
Seat's last result vs. expectation-1.07
Incumbent's last result vs. expectation0

Polls

R+15R+10R+5EvenD+5D+10D+15Avg. D+11.6Oct 1Nov 3
All 1 polls
PollsterDatesSampleStrattonTracyMarginAdjusted
Public Policy Polling for Chicago News WeeklyD-sponsoredSep 30–Oct 1569 LV4936D+13D+11.6

Adjusted: after correcting for the pollster's house effect, registered vs. likely voters, and movement in the national environment since the poll; shown for the polls carrying the most weight in today's average. Larger dots in the chart carry the most weight. Last poll: Oct 1, 2026.

The state

Lean D+13: how much more Democratic or Republican than the nation it votes for president.

Presidential vote

← RepublicanDemocratic →2016 presidentD+18.0D+15.8 vs. nation2020 presidentD+17.3D+12.8 vs. nation2024 presidentD+11.1D+12.6 vs. nation

Who lives here

Population
12,694,798
Adults with a B.A.+
38%
White, no degree
36%of adults
  • White 58%
  • Hispanic 19%
  • Black 13%
  • Asian 6%
  • Other / multiracial 4%

American Community Survey 2020–2024, aggregated from census tracts.

Past results

2024 President Vote in this state

5,511,942 two-party votes · D+11.1 · D+12.6 vs. the nation
✓ Kamala Harris (D)55.6%
Donald Trump (R)44.4%

2020

5,970,891 votes · D+17.1
✓ Richard J. Durbin (D)54.9%
Mark C. Curran Jr. (R)38.9%
Willie L. Wilson (OTH)4.0%
Danny Malouf (L)1.3%
David F. Black (G)0.9%

2020 President Vote in this state

5,918,806 two-party votes · D+17.3 · D+12.8 vs. the nation
✓ Joe Biden (D)58.7%
Donald Trump (R)41.3%

2016 President Vote in this state

5,236,744 two-party votes · D+18.0 · D+15.8 vs. the nation
✓ Hillary Clinton (D)59.0%
Donald Trump (R)41.0%

2014

3,603,475 votes · D+11.3
✓ Richard J. Durbin (D)53.5%
James D. "jim" Oberweis (R)42.7%
Sharon Hansen (L)3.8%

2008

5,329,883 votes · D+40.8
✓ Richard J. Durbin (D)67.8%
Steve Sauerberg (R)28.5%
Kathy Cummings (G)2.2%
Larry A. Stafford (L)0.9%

2002

3,486,851 votes · D+22.7
✓ Richard J. Durbin (D)60.3%
Jim Durkin (R)38.0%
Steven Burgauer (L)1.6%