2028 presidency — Marco Rubio

Polymarket prices Rubio at 15.15% — 3rd-highest behind Vance + Newsom. EHIQ revised UP to 10% from prior 8% after SEM v1.2 build (`sem-1.2-2026-05-22`). SEM v1.2 R-nomination probability = 21.27% (after long-lead compression x0.6 + withdrawal multiplier 0.20). Apples-to-apples presidency math: 21.27% × ~55% general ≈ 11.7%. 50% damping from prior: 8 + 0.5*(11.7-8) ≈ 9.85% → 10%. NOT TIQ-scored (no corpus in corpus_2026/us_2028_presidential/). SecState position + 2016/2024 donor network + Florida machine = establishment-pivot path if Vance falters. Range widened to 7-13% acknowledging structural-vs-thin-poll uncertainty.

• •Rubio register score (multi-source: 2024 RNC + 2016 announcement, Munich diplomatic excluded). Lowest hedging + lowest LAS of any R — most grounded register.
• •Polymarket 15.15% is high. Math sanity check: implied nomination probability ≈ 27% (15.15 / 55% gen). SEM v1.2 models nomination at 21.27% — closer to market but still below.
• •Establishment pivot scenario: if Trump or post-Trump R party wants competence + diplomatic gravitas, Rubio is the alternative. SecState role gives him cover Vance lacks.
• •PROBABILITY REVISION TIMESTAMPED 2026-05-22 (PART 2): EHIQ 8% → 10% after SEM v1.2 build. New SEM file `sem_us_president_2028_rubio.json` / `.prov.json`. SEM v1.2 R-nomination = 21.27% (raw P 10.98% → long-lead compression x0.6 → 26.6% → withdrawal multiplier 0.20 → 21.3%). Apples-to-apples ≈ 21.27% × 55% gen ≈ 11.7%. 50% damping from prior 8% baseline → 10%. NOT TIQ-scored (no corpus exists). §4 OOS Phase C FAIL still applies to broader engine. MARKET PROB ESTIMATE FLAG — Polymarket Rubio-as-R-nominee market price not directly verified in build session; 0.27 derived via /(0.55 gen) from presidency sub-market 0.1515.

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