Although it’s less consequential than the presidential debate, the VP debate saw more dramatic market uncertainty than its presidential counterpart.
Most of the money that entered the market came during the debate. On the morning of debate day, trading volume in Polymarket’s VP debate winner market was about $226,000. It reached just under $822,000 after the debate, well over three times the morning’s amount.
Similar amounts of money flooded the markets on words the candidates would say during the debate. Tim Walz and J.D. Vance “mention markets” saw trading volumes increase by 167% and 171% respectively from the morning of the debate to the minutes following it.
But the most dramatic moments were in the price movements themselves. Walz and Vance switched positions as the favorite on Polymarket five times during their debate.
Walz went into the debate as a favorite to win in part due to his high likability rating. However, Vance’s superior debating technique showed. His well-spoken answers and fluent polish made Walz’s everyman style of speech seem less sophisticated. Walz’s tendency to misspeak also came back to haunt him in key debate moments.
How Walz and Vance switched places as the favorite
Entering the debate, Walz enjoyed a high favorability rating, and Vance was known for remarks about Haitian immigrants eating cats and dogs.
The opening statements immediately changed the perceptions of the candidates. Walz spoke first and stumbled throughout his introduction. In contrast, Vance delivered a smooth campaign biography, defense of Donald Trump’s administration, and attacks on Harris’ and Biden’s records.
Before the opening statements, Walz had a 62% chance of victory, and Vance had a 38% chance of victory. Those prices flipped during Vance’s opening statement – a 24-point spike. Vance would peak at 66% and Walz would bottom out at 34%.
Then Walz found his rhythm. He spoke more fluently and mixed defenses of Harris with attacks on Trump. Walz began his recovery in his last word on climate change and energy policy. He spoke about how much more oil and natural gas the United States had produced during the Biden years while pitching an energy plan that thought ahead instead of only looking back.
Surprisingly, Walz solidified his gains during immigration, a topic that polls suggested Vance was stronger on. Vance focused his immigration responses on accusations that Harris opened the border while Walz spoke about addressing the fentanyl crisis and the bipartisan border bill that Trump killed. The immigration portion culminated in Vance arguing with the moderators and both candidates having their microphones cut while they argued with each other.
As the mics went silent, Vance was at 50% and Walz at 51%.
Walz answers become less specific, Vance takes control
Walz was the favorite through questions about the economy, defending previous false statements, and abortion rights. At the commercial break, Walz was the favorite 60% to 41%.
Then the debate turned to gun violence, and both candidates hovered around 50 cents. Vance took the lead by about one cent, then Walz took it back by a cent. At 8:11 MT, Vance retook a commanding lead. Walz had begun to speak less eloquently and failed to push back on Vance. In contrast, Vance maintained his polished performance and was careful to point out points on which he and Walz agreed.
Vance managed to come off as likable and courteous during the VP debate. Combined with his strong delivery and debate skills, he ended the debate as the clear favorite. At the debate’s end, Vance was the favorite to win 57% to 43%.
Mention markets had few surprises, revealed dumb money
The mention markets were popular among election bettors. After the debate, both markets saw trading volumes close to or above $1.25 million. Vance’s market was more volatile, though. The words that settled for Walz were priced at least at 70 cents the morning of the debate.
Vance had two words settle that were priced below 60 cents the morning of the debate. The odds of Vance saying “Kamala Harris” at least 30 times was priced at 59 cents, and saying “Donald Trump” at least 30 times was at 57 cents. The largest movements in word markets – whether they settled or not – are listed below:
| Market | Settle Status | Price Change from Debate Morning to Post-Debate |
|---|---|---|
| Walz - Dog | YES | 63 Cents Up |
| Walz - Helene | NO | 60 Cents Down |
| Vance - Trump 30+ | YES | 43 Cents Up |
| Vance - IVF | YES | 54 Cents Down |
Some of the word markets showed how influential memes were in many bettors’ minds. Both VP candidates had their own reasons to appeal calm, reasonable, and compassionate during the debate – especially Vance. Cats, tampon, and Haitian didn’t reach above 50 cents on debate day. These were based on viral stories of Vance’s worst outburst. Tampon, Haitian, and dog didn’t settle in Walz’ word market, either.
Second Harris/Trump debate odds drop further
The odds of a second debate between Harris and Trump dropped during the VP debate. When the debate started, Kalshi’s chance of another presidential debate sat at 29%. The odds fell to 23% after the debate. Vance delivered the calm, articulate debate performance that Trump couldn’t when he faced off against Harris. With little to gain and much to lose in a second debate, Trump now has soundbites and attack angles to defend some of his least popular moments.
Vance eloquently defended Trump’s record, even deflecting criticism of the Jan. 6 attack on the Capitol by pointing out that Trump left the White House on Jan. 20. Vance’s words painted a softer picture of Trump’s policies than Trump could ever do.
Walz’s performance left much to be desired compared to Harris’. Harris delivered precise attacks while Walz fell back on general points of agreement near the end of his debate with Vance.
Both VP candidates went out of their way to be conciliatory to contrast their debate with the presidential one. They succeeded, but it helped Vance much more than it did Walz. It’ll take time to understand the VP debate’s impact on the presidential race, but it was clear even in the minutes after the debate that the already low chances of a Harris/Trump rematch had fallen even lower.
