Scan: Will the Democrats win the Michigan Senate race in 2026?

date	predicted	market price	confidence
2026-08-22	66%	64%	60%
2026-08-15	54%	56%	52%

1. Planner Opus 5

Tools chosen: polymarket_direct kalshi_related polymarket_related claude_news claude_news gdelt_news wikipedia code_execution

Sub-questions (Fermi decomposition)

What is the current Polymarket price for Democrats winning the Michigan Senate seat, and how has it moved over the past 90 days?
What does Kalshi price the same Michigan Senate race at, and does it disagree with Polymarket?
Who are the leading Democratic and Republican candidates, and what do recent head-to-head general election polls (Rogers vs. Stevens/McMorrow/El-Sayed) show?
How do nonpartisan handicappers (Cook, Sabato, Inside Elections) currently rate the Michigan Senate seat, and has the rating shifted recently?
What is the national political environment as of now — generic congressional ballot margin, presidential approval, and Democratic overperformance in 2025 special elections?
What is the historical base rate for the out-party (Democrats) winning competitive open Senate seats in midterms under a Republican president, and how did Michigan's 2024 Senate race (Slotkin vs. Rogers) resolve?
Are there fundraising, candidate-quality, or third-party/independent entry developments that could shift the race?

Planner reasoning

This is a 2026 open-seat Michigan Senate race (Peters retiring) with a contested Democratic primary (Stevens, McMorrow, El-Sayed) and Mike Rogers as the likely GOP nominee, in a state Trump won narrowly in 2024. The Polymarket price is the primary anchor; cross-checks come from Kalshi's parallel market, current general-election polling, national environment indicators (generic ballot, special-election overperformance), and race-rating shifts.

2. Research

tool	status	time	items	summary
polymarket_direct	OK	0.5s	1	## This Market's Polymarket Data Will the Democrats win the Michigan Senate race in 2026? - Current price (probability): 64.50% - 7-day price change: +1.50% - 30-day price change: -3.00% - Total volume: $330,071 (USD notional) - Price range: 55.50% - 76.50% - Data points: 121 days
kalshi_related	OK	4.4s	3	3 related markets / summaries. keyword 'Michigan Senate': ok \| keyword 'Senate election 2026': ok \| keyword 'Senate control 2026': ok
polymarket_related	OK	0.1s	0	Scanned 100 active Polymarket markets, kept 0 matches. keyword 'Michigan Senate': 0 markets \| keyword 'Senate 2026': 0 markets \| keyword 'Democratic primary Michigan': 0 markets \| keyword 'Senate control': 0 markets
claude_news	OK	23.5s	18	## Key Findings: 2026 Michigan Senate Race - Primary results (Aug 4, 2026): The 2026 Michigan Senate race for the open seat vacated by retiring Sen. Gary Peters features Democrat Abdul El-Sayed and Republican Mike Rogers as nominees following the August 4 primaries, with El-Sayed edging Rep. H
claude_news	OK	24.1s	12	Based on available polling and election data as of late August 2026: National environment: - Generic congressional ballot polling shows a consistent Democratic lead. RealClearPolling's average has Democrats+6.4, with Democrats at 48.2% and Republicans at 41.8% (https://www.realclearpolling.co
gdelt_news	OK	73.7s	20	GDELT: 20 articles across 3 queries (lookback=45d). 'Michigan Senate race 2026 poll': 10 hits \| 'Mike Rogers Michigan Senate': error HTTPSConnectionPool(host='api.gdeltproject.org', port=443): Max retries exceeded with url: /api/v2/doc/doc?query=%28mike+OR+rogers+OR+michigan+OR+senate%29+sourcelang%
wikipedia	OK	0.2s	3	Fetched 3 Wikipedia entries (0 missing pages).
code_execution	OK	36.2s	0	## Findings - Market-implied odds: With an illustrative Polymarket YES = $0.62 / NO = $0.41 (overround = 1.030, i.e., ~3% vig), the de-vigged implied probability of a Democratic win is 60.2% (NO side de-vigs to 39.8%). - **Historical base rate (out-party in toss-up open Senate seats, oppos

3. Evidence Brief Sonnet 5, 6548 chars

# Current state The Nov 3, 2026 election will resolve this market once AP/Fox/NBC jointly call Michigan's Senate race (or after certification). Nominees are set: Democrat Abdul El-Sayed (won Aug 4 primary, 48.5%, over Rep. Haley Stevens) vs. Republican Mike Rogers (unopposed, 2024 nominee who lost narrowly to Slotkin). Public and internal polling since the primary shows a genuine toss-up, not a clear Democratic lead, despite prediction markets pricing Democrats as moderate favorites. # Timeline of key events - 2024-11-05: Elissa Slotkin (D) narrowly defeats Mike Rogers (R) by 0.34% for MI's other Senate seat — confirmed (Wikipedia). - 2026-07 (mid-month): Mallory McMorrow withdraws from Democratic primary, narrowing field to El-Sayed vs. Stevens — confirmed (Wikipedia). - 2026-07-15 to 08-01: Primary polling volatile — Stevens leads by 7 (Fox News poll, 07-15) then El-Sayed takes lead pre-primary (Newsweek, 08-01) — reported. - 2026-07-19/20: Sen. Sanders and Sen. Warren publicly back El-Sayed — reported (Fox, NY Post). - 2026-07-24/25: Gov. Whitmer endorsement in race noted — reported (RedState). - 2026-08-04: Primary held; El-Sayed wins Democratic nomination (48.5%); Rogers is unopposed GOP nominee — confirmed (Wikipedia). - 2026-08-11 to 08-20: Post-primary general polls diverge sharply — Fox News: Rogers 51-47; Susquehanna: El-Sayed +7; AARP: El-Sayed +1; local outlets (WXYZ etc.) report "El-Sayed holds slight edge" — reported. - 2026-08-14: RedState/Newsweek flag "warning signs" for El-Sayed re: electability — reported/opinion. - Ongoing (as of late Aug 2026): Cook Political Report and Sabato's Crystal Ball both maintain "Toss-up" rating; debate scheduling dispute (proposed Sept 15 debate) unresolved — reported. # Event Will the Democrats win the 2026 Michigan U.S. Senate race (El-Sayed vs. Rogers), resolved by AP/Fox/NBC race call or certification. # Outcomes to forecast Yes (Democrat wins) / No (Republican or other wins) # Kalshi market anchor No kalshi_direct data was returned for this ticker; the tool only surfaced unrelated/thematically-adjacent Kalshi markets (2028 Senate control futures, ~55-56% Dem). The ticker provided actually matches the **Polymarket** market exactly: current price 64.5% YES (Democrat), 7-day change +1.5%, 30-day change -3.0%, range 55.5%-76.5% over 121 days, volume $330K. Treat this 64.5% as the operative consensus anchor given the data available; a separate RealClearPolling citation shows Polymarket at 60-65% depending on date, consistent. # Sub-question answers 1. **Polymarket price/trend** — 64.5% currently; down from a high of 76.5%, up from a low of 55.5%; -3% over 30 days, +1.5% over 7 days (polymarket_direct). 2. **Kalshi price vs. Polymarket** — No direct Kalshi price for this exact market was retrieved; related Kalshi 2028 Senate-control markets price Dem control ~55-56%, roughly consistent in direction but not a direct comparison (kalshi_related). 3. **Candidates/polls** — El-Sayed (D) vs. Rogers (R). Head-to-heads split: Fox News Rogers+4, Susquehanna El-Sayed+7, AARP El-Sayed+1; PollingSource average R+0.3, DDHQ average El-Sayed+2 (claude_news, gdelt). 4. **Handicapper ratings** — Cook Political Report and Sabato's Crystal Ball both rate the race "Toss-up," unchanged through/after the primary (claude_news, centerforpolitics.org). 5. **National environment** — Generic ballot D+6 to D+8 (RealClearPolling, Silver Bulletin, DDHQ); Trump approval ~34% (Pew), net -19.5 (Silver Bulletin), historically weak for a midterm year (claude_news). No 2025 special-election overperformance data was retrieved (search limited). 6. **Historical base rate / 2024 MI race** — Out-party win rate in toss-up open Senate seats across 2006/2010/2014/2018 ≈56% (9/16), high variance by cycle (code_execution). Michigan's 2024 race: Slotkin (D) beat Rogers by just 0.34% while Trump carried the state (Wikipedia) — signals MI's Senate seat is more Dem-leaning than its presidential vote. 7. **Fundraising/candidate quality/third parties** — DDHQ flags El-Sayed as potentially the weakest Democratic Senate performer relative to 2024 baseline among tracked states; contentious primary (Sanders/Warren backing El-Sayed vs. establishment favoring Stevens) and "landlord socialist" attack lines suggest vulnerability (claude_news, gdelt). No major third-party entrant reported. # Key facts 1. [Wikipedia] Republicans haven't won a MI Senate race since 1994; this is the only Dem-held open seat in a Trump-2024 state. 2. [Wikipedia] El-Sayed won Dem primary 48.5% (Aug 4, 2026); Rogers unopposed for GOP. 3. [Wikipedia] Slotkin beat Rogers by 0.34% in 2024 while Trump won MI. 4. [PollingSource/claude_news] Post-primary polling average essentially tied (R+0.3 to D+2). 5. [Pollsmax] Model gives El-Sayed 53.5% win probability, "Tilt Democratic." 6. [Pew/Silver Bulletin] Trump approval historically weak (~34%, net -19.5) heading into midterms. 7. [RealClearPolling] Generic ballot averages D+6 to D+8. # Cross-market signals - Kalshi related: 2028 Dem Senate-control futures ~55-56%, directionally similar but different market/timeframe. - Polymarket (this market): 64.5% Yes, down from highs near 76.5%. - No sportsbook data retrieved. # Analyst opinions and speculation - Sabato: El-Sayed likely underperforms a generic Democrat but environment may compensate. - DDHQ: El-Sayed shows smallest Dem shift vs. 2024 among tracked Senate states — bearish signal for Dems. - Cook's Amy Walter: Dems have "multiple paths" to Senate majority even if MI is lost, implying genuine uncertainty about MI specifically. # Directional lean per outcome - **Yes (Dem win)**: Favorable national environment (generic ballot, weak Trump approval), MI's recent Dem Senate streak, market pricing 64.5%, model estimates 53-57%. - **No (GOP win)**: Toss-up polling averages (some show Rogers ahead), candidate-quality concerns about El-Sayed, smaller-than-expected Dem polling shift vs. 2024, contentious primary optics. # Gaps / unknowns - No confirmed direct Kalshi YES price for this exact ticker. - No 2025 special-election overperformance data. - Polling numbers cited in code_execution tool are explicitly illustrative/placeholder, not live figures — treat with caution. # Calibration anchors - Polymarket (de facto anchor for this ticker): 64.5% YES. - Blended quantitative estimate (market/polling/base-rate weighted): ~57% (range 51.5%-60.2%), per code_execution. - Historical base rate for out-party in toss-up open Senate seats: ~56% (high variance, 25-75% by cycle).

4. Forecasters Opus 5 + GPT-5.6 Sol, in parallel

claude-opus-5

52% conf

Yes	62%
No	38%

The operative market anchor (Polymarket, 64.5% YES, down from a 76.5% high but up 1.5% over 7 days) prices Democrats as moderate favorites, while post-primary head-to-head polling is essentially tied (Fox R+4, Susquehanna D+7, AARP D+1; averages R+0.3 to D+2) and both Cook and Sabato hold the race at Toss-up. Offsetting the tied polling is a strongly favorable national environment (generic ballot D+6 to D+8, Trump approval ~34%/net -19.5) plus Michigan's structural Democratic advantage in Senate races (no GOP win since 1994; Slotkin beat this same opponent, Rogers, even as Trump carried the state). The main bearish signal is candidate quality: DDHQ flags El-Sayed as the weakest Dem performer relative to 2024 baselines, and he emerged from a divisive primary with only 48.5%. I shade slightly below the 64.5% market toward the blended quantitative estimate (~57%) given genuinely tied polling and a proven, well-funded GOP nominee.

gpt-5.6-sol

67% conf

Yes	59%
No	41%

The operative market anchor is Polymarket's 64.5% Democratic probability, but essentially tied polling and toss-up ratings from both Cook and Sabato justify moving below that consensus. Democrats retain an edge from a favorable national environment, with a D+6 to D+8 generic ballot and deeply negative Trump approval, while Michigan has not elected a Republican senator since 1994. However, Rogers lost by only 0.34% in 2024, and concerns that El-Sayed may underperform a generic Democrat make this substantially more competitive than the market price implies. Overall, the evidence points to a modest rather than commanding Democratic advantage.

5. Devil's Advocate Sonnet 5

Both forecasters converge tightly (0.59–0.62) and neither explores the tail scenario where El-Sayed's "landlord socialist" attack lines and weakest-Dem-shift signal (DDHQ) compound with a low-turnout midterm to produce a larger-than-polling-implied miss, similar to how 2024 tied polls sometimes mask true movement in one direction — the brief's "high variance by cycle" base-rate note (25-75% range) suggests wider uncertainty bands than either forecast implies.

Neither forecaster grapples with the discrepancy between the Polymarket anchor (64.5%) and the model estimate (Pollsmax 53.5%, blended quantitative ~57%) beyond simple averaging — Forecast 1 lands at 62% (much closer to Polymarket) while Forecast 2 lands at 59%, but neither explains why they weight market vs. model differently, an inconsistency between the two that goes unaddressed.

Both treat the Kalshi/Polymarket distinction superficially; since no true Kalshi price exists for this ticker, forecasters should flag more explicitly that they are pricing a proxy market (Polymarket) with only $330K volume and a wide 55.5%-76.5% range over 121 days, indicating this is a thin, volatile market that may not deserve full anchoring weight.

Neither forecast addresses the debate scheduling dispute (proposed Sept 15 debate, "unresolved") as a potential volatility catalyst that could shift the race meaningfully between now and close — a relevant known unknown given the close time is Nov 3, 2026.

The primary's closeness (48.5%) and the Sanders/Warren vs. Whitmer/establishment split get mentioned as "electability" concerns but neither model quantifies how a fractured coalition might suppress moderate/establishment Democratic turnout in the general, which is a distinct risk from generic "candidate quality" framing.

Both forecasts anchor heavily on the generic ballot (D+6 to D+8) as bullish for Democrats, but neither notes that generic ballot advantages often compress in specific toss-up races with strong opposing name recognition (Rogers as a repeat, well-funded nominee) — this is a reference-class point neither forecaster interrogates given Amy Walter's comment that Dems have "multiple paths" to majority even losing MI, implying MI may be uniquely resistant to the generic-ballot tailwind.

6. Aggregator Opus 5

59% (60% confidence)

Yes: 59% No: 41%

The only usable anchor is a thin Polymarket contract (64.5%, $330K volume, 55.5–76.5% range), which deserves partial rather than full weight; quantitative models (Pollsmax 53.5%, blended ~57%) and tied post-primary polling (R+0.3 to D+2) sit meaningfully below it, and both Cook and Sabato hold the race at Toss-up. Democrats retain a real but modest edge from the national environment (generic ballot D+6 to D+8, Trump net approval ~-19.5) and Michigan's Senate history (no GOP win since 1994; Slotkin beat this same opponent in a Trump-carried state). Offsetting that, El-Sayed emerged from a divisive primary with 48.5%, DDHQ flags him as the weakest Dem shift versus 2024 baselines, and Rogers is a known, well-funded repeat nominee whose name recognition typically compresses generic-ballot tailwinds. The critique's points about a fractured coalition and cycle-level variance argue for humility, not a directional flip, so I settle just below both prior forecasts' midpoint and well below the market at 59%, with roughly two months of campaign volatility (debates, late shifts) still unresolved.

Pipeline Timing

Total pipeline time: 167.4s

Per-tool research timings shown in the Research section above.