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Reported remarks from Donald Trump about Vice President JD Vance have pushed 2028 Republican nomination prediction markets further toward a Vance-Marco Rubio contest.
According to the source report, Trump privately told donors, "we need to elect JD," a comment attributed to people familiar with the meeting and reported by The Washington Post. After that report, both Kalshi and Polymarket showed Vance with roughly a 20-point lead over Rubio in their GOP nominee markets.
Kalshi and Polymarket show Vance ahead of Rubio
Kalshi’s 2028 GOP nominee market had Vance at 42% and Rubio at 23%, with $56.1 million in volume. On Polymarket, Vance was at 43% and Rubio at 23%, with nearly $686 million in volume.
The source report said the two markets have increasingly separated Vance and Rubio after the pair had been running nearly even in June. It also described the Republican nomination market as effectively a two-person race between the vice president and Florida Sen. Rubio.
Trump has not made a formal endorsement. Publicly, he said it was "much too early" to be thinking about the 2028 election and called Vance "great," while advisers said no final decision has been made.
Markets and the straw poll are telling different stories
The market pricing contrasts with a recent Western Conservative Summit straw poll, where Rubio led with 57% support and Vance drew 21%.
Thomas Massie, Ron DeSantis and Mike Pence rounded out the top five in that straw poll. The gap suggests that activist sentiment in one event and real-money prediction markets are not moving in lockstep.
That split also shows up in broader 2028 winner markets. On Kalshi’s general election winner market, Vance stood at 19%, Rubio at 17%, and Gavin Newsom at 12%. On Polymarket, Vance was at 21%, Rubio at 13%, Alexandria Ocasio-Cortez and Newsom were each at 11%, and Jon Ossoff was at 10%.
What to watch next
The clearest next signal is whether Trump makes any more direct comments about Vance or Rubio. For now, the source report indicates markets are reacting to perceived preference rather than a formal endorsement, leaving plenty of room for prices to move as the 2028 race develops.
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Source: As reported by Pat Evans.
