Democrats winning all four core Senate seats near 50%

Name: Democrats winning all four core Senate seats near 50%
Creator: ClearMarket
Published: 2026-10-03T00:00:00.000Z
License: https://creativecommons.org/licenses/by/4.0/

Polymarket 54%

record: CMSIG2026100302 | category: momentum-repricing | target: CM-EVT-P54SDG6NP7 | published: 2026-10-03

4-bullet brief | narrative

Polymarket prices a 54% chance Democrats win all four core Senate races, barely above a coin flip.
Poll leads in multiple red states support a Democratic path, but the all-four-wins requirement keeps the Polymarket contract near 50%.
The gap between the 87% blue-wave Kalshi contract and this 54% contract reflects how difficult a clean sweep of all four targets remains.
Resolution via UMA oracle after November election results are confirmed.

atomic briefs | structured for retrieval

[01] news_event

significance

surfaced in the daily Exa news-cycle scan; mechanically matched to an active polymarket market

story: New polls show Democrats leading or tied in five reliably Republican states, raising the prospect of a Senate flip one month before midterms.exa_search → New York Times · as_of 2026-10-03T12:59:34+00:00
publisher: New York Times
published_at: 2026-10-03T00:00:00.000Z
source_url: https://dnyuz.com/2026/10/03/senate-races-in-republican-states-tilt-toward-democrats-polls-find/

[02] pm_response

interp: Polymarket's 54% on all four core Senate wins is the tightest read in the midterm cluster, underlining execution risk even in a wave environment.llm_judge_cm_signal_v1

evaluation

News-cycle wires publish on coverage, not editorial selection — the day’s top stories matched to the prediction markets pricing them, so nothing is cherry-picked.

judge_engine: none — deterministic news-cycle scan
judge_verdict: auto_published
judge_confidence: n/a — no judge gate (deterministic publishing)
prompt_template: news_cycle_v1 github · auditable
match_method: entity_slug_match (mechanical)

citation graph

Every wire traces back to the ClearMarket event it is built on, and out to each venue’s own market page — so any figure here can be verified at its source.

internal

cm_event: /events/will-democrats-win-all-core-four-senate-races/

external

venue_a: polymarket · 0x096f26b2abcfde3ee7863e7916ca17682522715f7631debd4878a43ee6c797a9

programmatic access · four surfaces, same payload

AI grounded search reads embedded JSON-LD in HTML. Developers query REST. Agentic AI clients (Claude Desktop, Cursor) call MCP tools. AI crawlers index via /llms.txt. Same canonical record at every surface.

HTML	browsers, AI grounded search, crawlers (contains embedded JSON-LD `@type: Dataset`)	`https://clearmarket.fyi/signals/dems-sweep-four-senate-races-polymarket-54-2026-10-03/`
JSON	REST API for developers	`https://clearmarket.fyi/signals/dems-sweep-four-senate-races-polymarket-54-2026-10-03.json`
MCP	agentic AI tool call (Claude Desktop, Cursor, Continue)	`clearmarket.get_signal("dems-sweep-four-senate-races-polymarket-54-2026-10-03")`
AGENT	AI crawler discovery index	`/llms.txt`

 PM data: platform APIs (hourly refresh). News context: retrieved with source citations. Editorial judgment: LLM judge with prompt template versioned per wire type. Per-claim provenance inline above; full per-field provenance map at the JSON endpoint under field_provenance.
  raw JSON record · same payload returned by REST endpoint
 {
  "$schema": "https://clearmarket.fyi/schema/signal/v1.json",
  "provenance_version": "0.2.0",
  "record_id": "CMSIG2026100302",
  "published_at": "2026-10-03T00:00:00.000Z",
  "detection": "news_cycle",
  "category_tag": "MOMENTUM_REPRICING",
  "secondary_tags": [],
  "pre_news_classification": "concurrent",
  "target_event_id": "CM-EVT-P54SDG6NP7",
  "target_event_slug": "will-democrats-win-all-core-four-senate-races",
  "event_question": "Will Democrats win all four core Senate races?",
  "bullets": [
    "Polymarket prices a 54% chance Democrats win all four core Senate races, barely above a coin flip.",
    "Poll leads in multiple red states support a Democratic path, but the all-four-wins requirement keeps the Polymarket contract near 50%.",
    "The gap between the 87% blue-wave Kalshi contract and this 54% contract reflects how difficult a clean sweep of all four targets remains.",
    "Resolution via UMA oracle after November election results are confirmed."
  ],
  "atomic_claims": [
    {
      "type": "news_event",
      "field_provenance": {
        "story": {
          "tier": "mediated",
          "method": "exa_search",
          "source": "New York Times",
          "source_url": "https://dnyuz.com/2026/10/03/senate-races-in-republican-states-tilt-toward-democrats-polls-find/",
          "retrieved_at": "2026-10-03T12:59:34+00:00"
        }
      },
      "significance": {
        "threshold": 5,
        "threshold_unit": "rank",
        "passed": true,
        "reason": "surfaced in the daily Exa news-cycle scan; mechanically matched to an active polymarket market"
      },
      "story": "New polls show Democrats leading or tied in five reliably Republican states, raising the prospect of a Senate flip one month before midterms.",
      "publisher": "New York Times",
      "published_at": "2026-10-03T00:00:00.000Z",
      "source_url": "https://dnyuz.com/2026/10/03/senate-races-in-republican-states-tilt-toward-democrats-polls-find/"
    },
    {
      "type": "pm_response",
      "field_provenance": {
        "notes": {
          "tier": "editorial",
          "method": "llm_judge_cm_signal_v1"
        }
      },
      "notes": "Polymarket's 54% on all four core Senate wins is the tightest read in the midterm cluster, underlining execution risk even in a wave environment."
    }
  ],
  "evaluation": {
    "judge_engine": "none — deterministic news-cycle scan",
    "judge_verdict": "auto_published",
    "judge_confidence": null,
    "prompt_template": "news_cycle_v1"
  },
  "citations": {
    "internal": {
      "cm_event": "/events/will-democrats-win-all-core-four-senate-races/",
      "related": []
    },
    "external": {
      "venue_a": null,
      "venue_b": null,
      "benchmark": null
    }
  },
  "sources": [
    {
      "label": "New York Times: Senate Races in Republican States Tilt Toward Democrats, Polls Find,",
      "url": "https://dnyuz.com/2026/10/03/senate-races-in-republican-states-tilt-toward-democrats-polls-find/",
      "published_at": "2026-10-03T00:00:00.000Z",
      "retrieved_at": "2026-10-03T12:59:34+00:00"
    }
  ],
  "field_provenance": {
    "pm_data": "polymarket_api",
    "news_context": "exa_search",
    "editorial_judgment": "cm_signal_llm_judge"
  }
}
 
   PROVENANCE PROTOCOL v0.2 · [direct] venue api · [mediated] grounded web fetch + source url · [derived] computed from listed inputs · [editorial] versioned llm judgment · full spec /schema/provenance/v1

record CMSIG2026100302 published 2026-10-03T00:00:00.000Z signature sha256-66aae40f43d… ← underlying event all signals →