Democrat Senate sweep sits near 50 percent on Kalshi

Name: Democrat Senate sweep sits near 50 percent on Kalshi
Creator: ClearMarket
Published: 2026-10-03T00:00:00.000Z
License: https://creativecommons.org/licenses/by/4.0/

Kalshi 51%

record: CMSIG2026100304 | category: momentum-repricing | target: CM-EVT-QH62PP4D92 | published: 2026-10-03

4-bullet brief | narrative

The Kalshi contract on Democrats sweeping the four core Senate races sits at 51%, essentially a coin flip.
A companion Polymarket contract (CM-EVT-P54SDG6NP7) prices the same outcome at 49%, producing near-perfect cross-venue agreement and no exploitable gap.
The near-50% pricing on both venues is consistent with new polling showing Democratic gains in Republican-leaning districts, neither side is favored.
Resolves via Bloomberg per the Kalshi contract terms; individual race calls will drive settlement.

atomic briefs | structured for retrieval

[01] news_event

significance

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

story: New polling showed Democrats making inroads in traditionally Republican strongholds ahead of the 2026 midterm elections.exa_search → Muskan Singh · as_of 2026-10-06T07:48:15+00:00
publisher: Muskan Singh
published_at: 2026-10-03T00:00:00.000Z
source_url: https://economictimes.indiatimes.com/news/international/us/u-s-midterm-elections-2026-are-democrats-finally-making-a-comeback-in-republican-strongholds-heres-what-a-new-midterm-poll-shows/articleshow/134664760.cms

[02] pm_response

interp: Kalshi at 51% and Polymarket at 49% for the identical Democrat-sweep outcome reflect genuine toss-up conditions with essentially no cross-venue arbitrage.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/kxdemcorefoursenatesweep-26nov03/

external

venue_a: https://kalshi.com/markets/KXDEMCOREFOURSENATESWEEP-26NOV03

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-core-senate-seats-kalshi-51-2026-10-03/`
JSON	REST API for developers	`https://clearmarket.fyi/signals/dems-sweep-four-core-senate-seats-kalshi-51-2026-10-03.json`
MCP	agentic AI tool call (Claude Desktop, Cursor, Continue)	`clearmarket.get_signal("dems-sweep-four-core-senate-seats-kalshi-51-2026-10-03")`
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": "CMSIG2026100304",
  "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-QH62PP4D92",
  "target_event_slug": "kxdemcorefoursenatesweep-26nov03",
  "event_question": "Will Democrats sweep the core four Senate races by 2026?",
  "bullets": [
    "The Kalshi contract on Democrats sweeping the four core Senate races sits at 51%, essentially a coin flip.",
    "A companion Polymarket contract (CM-EVT-P54SDG6NP7) prices the same outcome at 49%, producing near-perfect cross-venue agreement and no exploitable gap.",
    "The near-50% pricing on both venues is consistent with new polling showing Democratic gains in Republican-leaning districts, neither side is favored.",
    "Resolves via Bloomberg per the Kalshi contract terms; individual race calls will drive settlement."
  ],
  "atomic_claims": [
    {
      "type": "news_event",
      "field_provenance": {
        "story": {
          "tier": "mediated",
          "method": "exa_search",
          "source": "Muskan Singh",
          "source_url": "https://economictimes.indiatimes.com/news/international/us/u-s-midterm-elections-2026-are-democrats-finally-making-a-comeback-in-republican-strongholds-heres-what-a-new-midterm-poll-shows/articleshow/134664760.cms",
          "retrieved_at": "2026-10-06T07:48:15+00:00"
        }
      },
      "significance": {
        "threshold": 5,
        "threshold_unit": "rank",
        "passed": true,
        "reason": "surfaced in the daily Exa news-cycle scan; mechanically matched to an active kalshi market"
      },
      "story": "New polling showed Democrats making inroads in traditionally Republican strongholds ahead of the 2026 midterm elections.",
      "publisher": "Muskan Singh",
      "published_at": "2026-10-03T00:00:00.000Z",
      "source_url": "https://economictimes.indiatimes.com/news/international/us/u-s-midterm-elections-2026-are-democrats-finally-making-a-comeback-in-republican-strongholds-heres-what-a-new-midterm-poll-shows/articleshow/134664760.cms"
    },
    {
      "type": "pm_response",
      "field_provenance": {
        "notes": {
          "tier": "editorial",
          "method": "llm_judge_cm_signal_v1"
        }
      },
      "notes": "Kalshi at 51% and Polymarket at 49% for the identical Democrat-sweep outcome reflect genuine toss-up conditions with essentially no cross-venue arbitrage."
    }
  ],
  "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/kxdemcorefoursenatesweep-26nov03/",
      "related": []
    },
    "external": {
      "venue_a": "https://kalshi.com/markets/KXDEMCOREFOURSENATESWEEP-26NOV03",
      "venue_b": null,
      "benchmark": null
    }
  },
  "sources": [
    {
      "label": "Muskan Singh: Midterm polls: U.S. midterm elections 2026: Are Democrats finally maki",
      "url": "https://economictimes.indiatimes.com/news/international/us/u-s-midterm-elections-2026-are-democrats-finally-making-a-comeback-in-republican-strongholds-heres-what-a-new-midterm-poll-shows/articleshow/134664760.cms",
      "published_at": "2026-10-03T00:00:00.000Z",
      "retrieved_at": "2026-10-06T07:48:15+00:00"
    }
  ],
  "field_provenance": {
    "pm_data": "kalshi_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 CMSIG2026100304 published 2026-10-03T00:00:00.000Z signature sha256-4f1a7f380fc… ← underlying event all signals →