Robert F. Kennedy Jr. to win 2028 Republican presidential nomination

Step 1: Establish Base Rate

Historical base rate for Cabinet members challenging their own party's sitting Vice President after explicitly denying a run: effectively 0%.

Breaking this down:

• Sitting VPs seeking nomination win ~50-60% when they run; with strong establishment backing (like Vance has), this increases to ~70-80%
• Since 1972 (modern primary era), no former Democrat has won Republican nomination
• Insurgent challenges to establishment heirs (Buchanan 1992, etc.) can capture 15-25% of vote but have never secured nomination
• Politicians who issue explicit denials and then reverse course suffer credibility damage, especially problematic when serving in administration of the party's previous president

Combined base rate for someone in Kennedy's position: <1%

Step 2: Adjust for Specific Evidence

Factors decreasing probability from base rate:

• Explicit denial (August 2025): "I am not running for president in 2028" - only 7 months old, reversing would severely damage credibility with Trump base
• Structural disadvantage: Vance has massive institutional support (Rubio endorsement signal, 40-50% polling vs Kennedy's 7-8%)
• Party fit issues: Former Democrat, environmentalist past, anti-vaccine stances create heavy GOP establishment baggage
• Currently serving: As HHS Secretary, running would require leaving administration or awkward campaign-while-serving scenario
• Delegate math: Even Buchanan-style insurgency (23% of vote) doesn't translate to nomination under modern rules

Factors slightly increasing probability:

• Super PAC infrastructure: Mid-2025 organizing calls suggest some groundwork exists despite denials
• MAHA movement: "Make America Healthy Again" brand could resonate with populist wing
• Time horizon: 22 months until primaries is substantial period for landscape shifts
• Vance hasn't formally declared: Small chance Vance doesn't run, opening field (though highly unlikely)

Step 3: Scenario Modeling

The question asks if Kennedy will "win" the nomination, not merely run. This requires:

1. Reversing his explicit denial
2. Actually entering the race
3. Defeating Vance (or successor frontrunner) in primaries
4. Securing delegate majority at convention

Each of these is a compounding probability barrier.

Step 4: Compare to Market

Market implies 0.85% probability. This appears well-calibrated given:

• Multiple compounding low-probability events required
• Strong structural barriers
• Recent, unambiguous denial
• Overwhelming frontrunner with institutional backing

Step 5: Edge Assessment

My estimate of ~0.8% is nearly identical to market's 0.85%. The market appears efficient here. The slight uncertainty comes from:

• Long time horizon (22 months)
• Super PAC activity suggesting some infrastructure
• Political unpredictability in Trump-era GOP
• Small chance of Vance not running

However, these factors are likely already priced in. No meaningful edge detected.

No meaningful edge detected.

My estimated probability of ~0.8% is nearly identical to the market's 0.85% implied probability. The market appears well-calibrated for this question.

The extremely low probability (<1%) appropriately reflects multiple compounding barriers:

• Reversing explicit denial (maybe 10-15% chance he even enters)
• Defeating overwhelming frontrunner with institutional backing (even if he runs, maybe 5-10% chance of winning)
• Compounded probability: 0.12 × 0.07 ≈ 0.008 or 0.8%

Reasons the market is likely efficient here:

1. High-profile question with clear public information (Cabinet position, polling, denial statement)
2. Long time horizon is priced in through existing uncertainty
3. Market has access to same information about Vance's advantages and Kennedy's barriers
4. 0.85% appropriately captures "possible but highly unlikely" scenario

Minor considerations:

• If you have strong conviction that Vance won't run (not suggested by evidence), Kennedy's probability increases to ~3-5%, creating potential edge
• If you believe Trump will eventually endorse Kennedy over Vance (no evidence for this), there could be value
• Market could be slightly underpricing pure political chaos over 22-month horizon

Recommendation: No bet. Market is fairly priced. The 0.85% odds appropriately reflect the extremely low but non-zero probability of this outcome. Would only consider betting if odds drift above 2% (overpricing unlikely scenario) or below 0.3% (underpricing long-shot chaos potential).