Scan: Will the margin of victory for Juliana Stratton in the 2026 Illinois Democratic Senate primary election be between 6% and 9%?

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Will the margin of victory for Juliana Stratton in the 2026 Illinois Democratic Senate primary election be between 6% and 9%? — Stratton, 6-9%

KXMOVILSENATED-26MAR17-JSTR-P7 · Elections · 2026-04-14

96%

Agent

97%

Market Price

-1.1%

Edge

93%

Confidence

Volume: 61,678

Spread: 2.5c

Days to resolution: 337

Markets in event: 13

Final Rationale

The Illinois Democratic Senate primary occurred on March 17, 2026 — nearly a month ago. Stratton won with 40.2%, and the market surged from ~12% to 97% immediately after, with high volume (2203 daily contracts) and deep orderbook (4696 depth), strongly indicating that publicly available certified results confirm the margin falls in the [6%, 9%) bracket. I ACCEPT the Devil's Advocate critiques: (1) my independent estimate had a math error (0.99×0.97×0.45=0.43, not 0.74), (2) my sq3 estimate of 45% severely underweighted the post-event market signal, and (3) the 'base rate' ensemble perspective was inappropriate for an already-occurred event. The final poll showed Krishnamoorthi at ~31.6%, implying a margin of ~8.6% — inside the bracket — and the market confirms this with near-certainty. I discount slightly from 97% to 96% only for the tiny possibility of a recount or data correction shifting the margin outside the bracket boundary.

Price vs. prediction

How the market moved after the agent's call. Solid blue line is the actual market price; dashed line is the agent's static forecast at $t{=}0$.

$n = 37$ follow-ups

1. Planner Opus · Fermi decomposition + tool plan

Tools chosen: kalshi_data kalshi_orderbook article_search web_search wikipedia_lookup code_execution

Sub-questions (Fermi decomposition)

Will Juliana Stratton win the 2026 Illinois Democratic Senate primary election? (w=0.30)
Will the margin of victory in the 2026 Illinois Democratic Senate primary be relatively close (under 15%)? (w=0.40)
Given a competitive primary, will Stratton's margin of victory specifically fall in the 6-9% range? (w=0.30)

Planner reasoning

This is a bracket question asking whether Stratton's margin of victory falls in a specific narrow 3-percentage-point band (6% to 9%). The key challenges are: (1) Will Stratton win at all? (2) If she wins, what does the margin distribution look like? Reference classes: Illinois statewide Democratic primaries where a LG/incumbent-adjacent figure runs. Illinois Democratic primaries for Senate seats (2004 Obama, 2010, 2014, 2017 special, 2020 Durbin) show varying competitiveness. When a well-known Democrat (LG, former officeholder) runs, they often win by large margins unless there's a strong challenger. Causal mechanisms: Stratton as incumbent Lt. Governor has statewide name recognition and institutional support (endorsements from Gov. Pritzker likely). However, Senate primaries attract strong challengers, and Illinois has active progressive/moderate factions. The 6-9% range suggests a moderately competitive primary - not a blowout but not extremely close. What makes this hard: Illinois Senate primaries with clear frontrunners often result in 20%+ margins; close races cluster near 0-5%. The 6-9% band is a specific 'middle ground' that requires a particular competitive dynamic. The primary is March 17, 2027 - over 11 months away. No polling data likely exists yet. Temporal analysis: The primary is March 17, 2027 (337 days away). Candidate filing deadlines in Illinois are typically November 2026. Polls won't be meaningful until late 2026. The sequence: (1) Who else enters the race? (2) Do any major challengers (progressive Rep, wealthy self-funder) gain traction? (3) What endorsements does Stratton secure? (4) Does the race remain competitive or become a blowout? The prior for any specific 3pp margin band is inherently low (~5-10%), modified by whether the race is competitive vs. a blowout. Given Stratton's incumbency advantage as LG, a blowout seems more likely than a close race, making this specific band even less probable.

2. Research Parallel tool calls · legacy v2

Tool	Status	Time	Items
kalshi_data	OK	1.9s	-
kalshi_orderbook	OK	0.3s	-
article_search	OK	0.3s	-
web_search	OK	57.0s	-
wikipedia_lookup	OK	1.8s	-
code_execution	OK	0.0s	-

3. Evidence Synthesis Sonnet · 11 items · legacy v2

#	Strength	Credibility	Direction	Source	Claim	Priced In
1	STRONG	92	↑ UP	web_search	Juliana Stratton won the Illinois Democratic Senate primary on March 17, 2026, with 40.2% of the statewide vote, defeating Representatives Krishnamoorthi and Kelly.	Yes
2	STRONG	88	↑ UP	wikipedia_lookup	The Wikipedia article on the 2026 Illinois Senate election confirms Stratton won the Democratic primary and is now the Democratic nominee facing Republican Don Tracy in the general election.	Yes
3	MODERATE	72	NEUTRAL	web_search	Final pre-election poll (March 13-15, 2026) showed Krishnamoorthi at 31.6% and Stratton at 29.4%, within the margin of error, indicating a very close race heading into primary day.	Yes
4	MODERATE	80	NEUTRAL	web_search	Stratton won with 40.2% of the vote in a three-way race; the exact margin over Krishnamoorthi is not fully specified in the data, but she secured 47 counties including Cook and Will.	Yes
5	MODERATE	70	↑ UP	web_search	Pre-election polls showed the race extremely close — Stratton at ~29-38% and Krishnamoorthi at ~31-39% depending on the poll and timing, suggesting the margin of victory was likely small.	Yes
6	MODERATE	70	↑ UP	web_search	Kelly (third candidate) polled at 13.6% in the final pre-election poll, meaning the vote was split three ways, which could compress Stratton's margin over Krishnamoorthi.	Yes
7	STRONG	88	↑ UP	kalshi_data	The Kalshi market for 'Stratton, 6-9%' (KXMOVILSENATED-26MAR17-JSTR-P7) is priced at 97.10%, with a 30-day price change of +85.10%, suggesting the market believes the result is nearly confirmed.	No
8	STRONG	85	↑ UP	kalshi_orderbook	The orderbook shows yes_bid at $0.05, no_bid at $0.00, spread of $0.947, with high liquidity (depth=4696), suggesting the market is nearly fully resolved to YES with minimal counterparty interest in NO.	No
9	STRONG	87	↑ UP	kalshi_data	The 30-day price movement of +85.10% (from ~12% to ~97%) indicates this market moved dramatically after the March 17 primary result became known, consistent with a confirmed outcome.	No
10	WEAK	35	↓ DOWN	code_execution	Prior probability modeling estimated P(Stratton wins AND margin is 6-9%) at approximately 4.4%, based on uniform distribution assumptions before the election result was known.	Yes
11	MODERATE	72	↑ UP	web_search	Stratton won with 40.2% of the vote; if Krishnamoorthi received approximately 31-34% (consistent with final polls), the margin would be approximately 6-9 percentage points, fitting the bracket.	Yes

Information Gaps

The exact final vote percentages for Krishnamoorthi and Kelly in the March 17 primary are not fully reported — we have Stratton at 40.2% but not the runners-up totals needed to confirm the exact margin.
No official certified election results or AP/major wire call with full vote totals by candidate has been cited in the research data.
No independent (non-internal) final vote tally source is provided — only Stratton's percentage and county wins are mentioned.
The web search result was truncated after mentioning Stratton's percentage, cutting off before reporting runner-up results.

Key Uncertainties

The exact margin between Stratton and Krishnamoorthi is the critical unknown — the Kalshi market at 97.1% strongly implies the margin fell in the 6-9% range, but the raw vote data to confirm this is not fully visible in the research.
Whether the 40.2% Stratton total and polling-implied ~31-34% for Krishnamoorthi translates precisely to a 6-9% margin depends on final certified vote counts.
The Kalshi market price of 97.1% could reflect either confirmed results or very strong expectation based on partial returns — the distinction matters for certainty level.
Kelly's final vote share affects the two-candidate margin calculation — if Kelly overperformed relative to polls, it could compress or expand the Stratton-Krishnamoorthi margin.

Market Context

Price: 0.971 · 7d: +0.031 · 30d: +0.851
Volume: HIGH — 2203 average daily contracts is substantial for a state-level primary bracket market · Depth: HIGH — depth of 4696, yes_bid at $0.05, no_bid at $0.00, indicating market is nearly fully settled
Reliability: HIGH — the dramatic 30-day price surge from ~12% to 97% with high volume strongly suggests the primary result occurred and confirmed the 6-9% margin bracket; this is the most actionable signal in the dataset

4. Independent Forecaster Opus · No market price · legacy v2 Did NOT see market price

Independent estimate: 74% (56% confidence)

base rate

45%

35% conf

evidence driven

91%

72% conf

contrarian

87%

62% conf

Spread

46pp

High disagreement

sq1: Will Juliana Stratton win the 2026 Illinois Democratic Senate primary election?

99%

This has already happened. Multiple sources confirm Stratton won the primary on March 17, 2026 with 40.2% of the vote. This is essentially certain.

sq2: Will the margin of victory be relatively close (under 15%)?

97%

Stratton won with 40.2% in a three-way race. Given Kelly polled at ~13.6%, the remaining ~60% was split between Krishnamoorthi and Kelly. For the margin to exceed 15%, Krishnamoorthi would need <25.2%, which is far below all polls showing him at 31-39%. Virtually certain the margin was under 15%.

sq3: Given a competitive primary, will Stratton's margin specifically fall in the 6-9% range?

45%

This is the key uncertainty. Stratton at 40.2% means second place needs to be between 31.2% (for exactly 9% margin, exclusive) and 34.2% (for exactly 6% margin, inclusive). The final poll had Krishnamoorthi at 31.6%, which would place the margin at ~8.6% - inside the bracket. However, polls can be off by several points. If Krishnamoorthi got 31-34%, we're in the bracket. If he got 30% or below, the margin exceeds 9%. If he got 35%+, margin is under 6%. The polling evidence clusters around 31-32% for Krishnamoorthi, putting us likely inside or just at the upper edge of this bracket. But there's meaningful uncertainty about whether the exact margin is 6.0-8.99% vs slightly outside. The information gap about exact results is significant. However, given the polling convergence around 31-32% for Krishnamoorthi, an 8-9% margin seems most likely, which is right at the boundary. I estimate ~45% probability the margin falls precisely in [6%, 9%).

Show full reasoning trace

base rate: For any specific 3-point margin band, prior probability is ~10-15%. But this election already occurred, so we update heavily on actual results.

evidence updates: Stratton at 40.2% confirmed. Final polls had Krishnamoorthi at ~31.6%, implying ~8.6% margin (inside bracket). But polls have ~3-4% error, creating real uncertainty about whether actual margin is in [6,9) vs outside.

combination method: Conditional chain, dominated by sq3 since sq1 and sq2 are near-certain.

final: The election happened, Stratton won at 40.2%. The exact second-place percentage is unknown but polling suggests ~31-32%, placing the margin likely around 8-9%. This is near the upper boundary of the bracket, creating substantial uncertainty. I estimate 45%.

ensemble: {'ensemble_count': 3, 'perspectives': {'base_rate': {'p_yes': 0.45, 'confidence': 0.35}, 'evidence_driven': {'p_yes': 0.91, 'confidence': 0.72}, 'contrarian': {'p_yes': 0.87, 'confidence': 0.62}}, 'spread': 0.46, 'individual_p_yes': {'base_rate': 0.45, 'evidence_driven': 0.91, 'contrarian': 0.87}}

5. Devil's Advocate Sonnet · legacy v2 Market price revealed

Math Error Asymmetric Evidence Reasoning Flaw Missing Info

Challenges

The market is at 97% with high volume and liquidity, having surged from ~12% to 97% after the March 17 primary. This is a post-event market where results are known to participants. The forecaster acknowledges Stratton won with 40.2% but claims not to know the exact second-place finish. However, the market behavior (settling at 97%) is extremely strong evidence that the actual margin IS in the 6-9% bracket - this is essentially a resolved market waiting for official certification.
The forecaster's combined probability of 0.743 is mathematically inconsistent with their own sub-question estimates. P(sq1) × P(sq2) × P(sq3) = 0.990 × 0.970 × 0.450 = 0.432, not 0.743. The ensemble method then pushes this up to 0.743 by averaging with 'evidence_driven' (0.91) and 'contrarian' (0.87) perspectives, but these higher estimates aren't well-justified given the sq3 estimate of 0.45.
The forecaster's sq3 estimate of 45% significantly underweights the available evidence. The final poll showed Krishnamoorthi at 31.6%, which would place the margin at ~8.6% - squarely inside the bracket. Moreover, the market at 97% with 2203 daily contracts and a +85% 30-day move is overwhelming evidence that the actual results confirmed this bracket. The forecaster treats the exact result as highly uncertain when in reality thousands of market participants with access to actual vote tallies have priced this at near-certainty.
The forecaster identifies 'information gaps' about exact vote totals, but this is a gap in THEIR research, not in publicly available information. The primary occurred nearly a month ago (March 17, 2026). Official results are publicly available. The market participants clearly have access to these results. The forecaster should have weighted the market signal much more heavily as evidence that the actual margin falls in 6-9%.
The ensemble approach is flawed: the 'base_rate' perspective at 0.45 makes no sense for a question about an event that has already occurred and whose result is known to market participants. Base rates are irrelevant when you have direct evidence of the outcome.

Suggested adjustment: +22pp

The math error (0.99 × 0.97 × 0.45 = 0.43, not 0.74) and the severe underweighting of post-event market evidence both point to a much higher probability. The primary occurred a month ago; results are publicly known. A high-volume, high-liquidity market at 97% after a dramatic post-election surge is near-definitive evidence that the margin fell in the 6-9% bracket. The only residual uncertainty is potential data entry errors or recounts, which justifies a small discount from 97% but not a 22+ point discount. The forecast should be approximately 0.95-0.96.

Market comparison: Forecaster: 74.3%, Market: 97.1%. The 22.8% divergence is NOT justified. This is a post-event market where the primary occurred on March 17, 2026 — nearly a month ago. The market's dramatic surge from ~12% to 97% with high volume after the election date is strong evidence that the actual certified results confirm the 6-9% margin bracket. The forecaster has no genuinely new information suggesting the market is wrong; rather, they have an information gap (not knowing exact runner-up totals) that market participants have clearly filled. The forecaster should defer heavily to the market signal here.

6. Aggregator Opus · final calibrated forecast

96% (93% confidence)