Secretary of State Marco Rubio has emerged as one of the leading contenders in early speculation surrounding the 2028 presidential election, with a major prediction market briefly placing him as the most likely winner of the upcoming White House race. Rubio's surge comes at a time when Vice President J.D. Vance, once viewed as the clear Republican heir apparent, has experienced a noticeable decline in prediction market confidence. Prediction markets put Rubio on top U.S.