Vice President JD Vance’s prospects for the 2028 presidential race have hit a historic low as the U.S.-led war in Iran enters its second month, triggering a sharp shift in both prediction markets and traditional betting odds.
As of March 29, 2026, Vance’s implied probability of winning the White House has collapsed to 18% on Polymarket and 19.2% on Kalshi. These figures represent the lowest standing for the Vice President since the Trump administration returned to power in 2024. For the first time in nearly two years, a Democrat—California Governor Gavin Newsom—is now the betting favorite in several major markets.
The Numbers: A Field in Flux
The downturn for Vance coincides with a surge for rivals across the political spectrum. On Polymarket, where more than $455 million has been traded on the 2028 race, Vance’s odds crashed from a February high of 22.4% to his current 18%.
- Gavin Newsom (D): Narrowed the gap to 17% on Polymarket and 18.3% on Kalshi.
- Marco Rubio (R): Holds steady at 11-14% after a brief spike following the initial strikes on Tehran.
- Alexandria Ocasio-Cortez (D): Remains a speculative outlier at 5%, though her market has attracted over $10 million in trading volume.
Traditional bookmakers are reacting even more aggressively. Star Sports now lists Newsom as the 7/2 favorite, overtaking Vance (4/1) for the first time since the 2024 election.
The “Iran Factor” and Domestic Headwinds
Analysts attribute the decline to the escalating geopolitical crisis in the Middle East. While President Trump announced a 10-day pause in energy strikes on March 27 to facilitate negotiations, the conflict continues to widen. The recent entry of Houthi rebels into the war and reports of the Pentagon preparing for potential ground operations have unsettled investors.
Domestic economic pressure is also mounting. Recent polling indicates that rising gas prices—driven by the closure of the Strait of Hormuz—are souring voter sentiment. “The shift reflects a combination of polling trends and broader political headwinds,” said William Kedjanyi, a political analyst at Star Sports. “Newsom currently leads Vance in head-to-head polling averages by roughly 4.6%.”
Looking Ahead
Despite the slide in general election odds, Vance remains the front-runner for the Republican nomination at 11/8. However, his once-indomitable “MAGA” coalition is showing signs of fragmentation as Secretary of State Marco Rubio gains steam, recently surging to 35% in a CPAC straw poll.
The 2028 landscape remains volatile, tethered heavily to the outcome of the ongoing diplomatic talks scheduled to conclude—or collapse—by April 6.
