6% — Will Marco Rubio and Byron Donalds be the 2028 Republican Presidential ticket Kalshi 6% · 10 contracts · $240 volume · medium confidence Updated 2026-06-08 05:27:39 UTC Why this matters: This probability represents the chance that Marco Rubio and Byron Donalds will run together as the Republican presidential and vice-presidential nominees in 2028. The 5% estimate reflects several structural challenges: Rubio currently serves as Secretary of State, which typically limits presidential ambitions, and separate contract markets show only 23% odds he becomes the presidential nominee at all. The pairing faces additional difficulty since Donalds, a U.S. Representative from Florida, would need to establish significantly higher national profile. The main factors affecting this probability are Rubio's political trajectory over the next 18 months—whether he remains in the cabinet, leaves early, or pivots toward electoral politics—and whether Republican primary dynamics favor a ticket with two Florida-based candidates. The 2028 Republican National Convention in summer 2028 will ultimately resolve this question, though the nomination outcome will be determined through primary elections and delegate selection processes beginning in early 2028. Key factors: - Rubio's current role as Secretary of State and whether he departs the cabinet before the 2028 cycle, as current markets price only 19% probability he leaves before 2027 - Separate markets show only 23% odds Rubio becomes Republican presidential nominee, suggesting the baseline probability of any specific VP pairing is constrained - Byron Donalds has not yet been nominated for Florida governor per available markets (86% odds), making a vice-presidential nomination less likely without higher state-level credential - Two nominees from the same state would be historically unusual for a major party ticket, creating structural disadvantage - The Republican primary process beginning early 2028 will determine the nominee and their running mate selection Contracts: - Will JD Vance and Erika Kirk be the 2028 Republican Presidential ticket?: JD Vance and Erika Kirk — 3¢ Kalshi $237 (weight 98%) - Will JD Vance and Marco Rubio be the 2028 Republican Presidential ticket?: JD Vance and Marco Rubio — 22¢ Kalshi $4 (weight 2%) - Will Marco Rubio and JD Vance be the 2028 Republican Presidential ticket?: Marco Rubio and JD Vance — 10¢ Kalshi $0 (weight 0%) - Will JD Vance and Sarah Huckabee Sanders be the 2028 Republican Presidential ticket?: JD Vance and Sarah Huckabee Sanders — 3¢ Kalshi $0 (weight 0%) - Will Marco Rubio and Glenn Youngkin be the 2028 Republican Presidential ticket?: Marco Rubio and Glenn Youngkin — 3¢ Kalshi $0 (weight 0%) - Will JD Vance and Donald Trump be the 2028 Republican Presidential ticket?: JD Vance and Donald Trump — 3¢ Kalshi $0 (weight 0%) - Will Marco Rubio and Elise Stefanik be the 2028 Republican Presidential ticket?: Marco Rubio and Elise Stefanik — 3¢ Kalshi $0 (weight 0%) - Will Donald Trump Jr. and Marco Rubio be the 2028 Republican Presidential ticket?: Donald Trump Jr. and Marco Rubio — 3¢ Kalshi $0 (weight 0%) - ... and 2 more --- ## Methodology SimpleFunctions aggregates live YES-side prices from Kalshi and Polymarket contracts bound to this question. For binary topics the headline is the liquidity-weighted mid-price (weight = log(1 + 24h volume) × freshness, where freshness is 1.0 if updated <24h, 0.7 if <7d, 0.4 otherwise). For multi-outcome (winner-take-all) topics the headline is the current leader's price — disjoint outcomes are never arithmetically averaged. Snapshots refresh every 5 minutes during market hours. ## SF Signal - SF Index, regime, and 30d Brier calibration are computed separately and surfaced at https://simplefunctions.dev/admin/calibration. - No SimpleFunctions index / regime / calibration signal is bound to this topic yet — the headline above is market-derived only. --- *Last verified: 2026-06-08T05:20:12.148Z* By SimpleFunctions — https://simplefunctions.dev/ Cite as: "6% per prediction markets (SimpleFunctions, June 2026)" Canonical: https://simplefunctions.dev/answer/rticket Full data: https://simplefunctions.dev/api/public/query?q=Will%20Marco%20Rubio%20and%20Byron%20Donalds%20be%20the%202028%20Republican%20Presidential%20ticket Provider: SimpleFunctions — https://simplefunctions.dev