ME Senate — Collins (R) retention
Will Susan Collins (R) retain her Maine Senate seat in 2026?
EHIQ reads a lower probability than Polymarket by 1.5pp. What triggers a review: Re-mark to 0.25 if any two fire: (a) RCP average >= Jackson +5 on Oct 15; (b) two live-caller polls (UNH/Emerson/CNN class) show Jackson +6 after Oct 1; (c) Polymarket Collins <= 0.20 for 5 consecutive sessions. Re-mark up only if RCP average shows Collins ahead on/after Oct 1..
Provenance: EHIQ registered 50% on Jul 26, 2026, no market at registration (prereg'd, evidence-grade).
+The argument — why we think itthe thesis and the reasoning behind the call
↗️ EHIQ LEAN: Collins stronger than expected (+3.5pp) September 2026 rebuild for the Jackson matchup — the prior text tested a withdrawn candidate (Platner withdrew July 10; Troy Jackson nominated at the July 25 convention). The September polls say a true toss-up: UML's survey center (Sep 24) has Jackson 46-45, while WABI/Maine Public the same week has Collins +3 — a 4-point spread inside ten days. Collins's favorability is underwater 10-19 points in three houses (Emerson 38/57, UNH 35/53, CNN 41/51); Cook, Sabato, Inside Elections and DDHQ all sit at toss-up or Lean D. What keeps this at 40 and not at the market: the documented Collins-specific polling miss — she has outrun her polls in every one of her five Senate races, and Maine's ranked-choice-ish split electorate breaks late for incumbents with her profile. EHIQ 40% vs Polymarket 36.5%.
- •Restated 2026-09-20 (0.50 -> 0.40): rebuilt for Collins vs Troy Jackson. Basis: 9-poll post-convention average Jackson +2.3 (RCP +1.8 / Silver Bulletin +3.5); favorability from three pollsters; 4 of 4 raters toss-up or better for Democrats; ad reservations $60M vs $24M (AdImpact); Jackson has never won statewide; Collins outran her 2020 polls by 17.7 points.
+The evidence — markets, embeds, data notestracked markets, embed code, and the as-of/liveness detail
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