This is an excerpt of Sources by Alex Heath, a newsletter about AI and the tech industry, syndicated just for noti.group subscribers once a week.
At 8PM on election night in New York City, I arrived at an unmarked office building in the Meatpacking District.
Inside, a few dozen young Kalshi employees moved between clusters of desks, pizza boxes, and a large projector displaying live markets for the day’s key races. The vibe was quiet but focused. On the screen, numbers flickered as bets adjusted in real time.
Near the projector, co-founders Tarek Mansour and Luana Lopes Lara chatted with a CBS News crew filming a segment for the next morning. CBS had just called the Virginia governor’s race. Mansour pointed out that Kalshi’s market had predicted the result almost an hour earlier.
“We’re doing a billion dollars in transaction volume a week now.”
I expected a trading floor atmosphere. Instead, the office felt subdued. “I think it’s quieter than usual because there’s less volatility on this one,” Mansour told me later from a small conference room. The New York mayor’s race had long been priced as a landslide. Zohran Mamdani had held a roughly 95 percent chance of winning on Kalshi (and its rival Polymarket) even before polls closed. Still, about $100 million in trades on the New York race went through Kalshi that day.
In recent months, I’ve been tracking the rise of prediction markets and particularly Kalshi. Despite being federally licensed and much larger than Polymarket, it’s the latter that dominates the conversation in tech circles. Mansour wants to change that.
“Kalshi is arguably one of — maybe the — fastest-growing companies in America this year,” he told me. “We’re doing a billion dollars in transaction volume a week now.” Last year, the company saw just $300 million for the entire year. Mansour declined to share revenue figures, but even at a 1–2 percent fee per trade, the math suggests that business is booming.
Three factors have fueled that growth this year: securing a federal license to operate, expanding into sports betting, and striking a partnership with Robinhood to power prediction markets. While sports have been a major draw, Mansour’s ambitions go far beyond that.
“I think prediction markets are the next generation of the stock market,” he said. “They have media consequences. Everyone is an expert on something — everyone has opinions. These markets give those opinions a price.”
Kalshi called the New Jersey governor’s race 32 minutes before any news outlet
He hinted at new partnerships with media outlets and even entertainment event tie-ins. “We’re doing a lot with news networks in the coming months,” he said. “If the truth that comes out of these markets becomes mainstream, we’ve basically achieved our mission.”
Given how new prediction markets are, Kalshi and Polymarket still need to prove that they can remain reliable sources for predicting elections. Fox News took a reputational hit for accidentally calling Arizona for Joe Biden too early in 2020. Meanwhile, Kalshi and Polymarket brag about calling races even before results are in. If one of them gets a key race wrong, it could call into question the legitimacy of prediction markets.
With less than an hour left before polls closed, Mansour showed me Kalshi data from the New York mayoral race. Voters in the city were buying Andrew Cuomo contracts more heavily, but Mamdani dominated elsewhere. He was winning among women and younger traders; Cuomo’s support skewed older and male.
As we spoke, Kalshi called the New Jersey governor’s race at 8:20PM — 32 minutes before any news outlet. Mansour compared Kalshi’s role to that of financial markets: “Should the stock market replace bank analysts? No. Analysts provide input, and the market finds the real price. We’re doing the same thing for events.”
I asked whether people constantly text him for predictions, especially on an election night. He laughed. “Yeah. But I tell them: just look at the market. I don’t have any extra information.”
As 9PM neared, I assumed he’d stay in the office as polls closed. But as I stepped into my Uber, I saw him dart out and get into another car down the street.
He didn’t need to wait. Kalshi called the New York race for Mamdani one minute after polls closed and 36 minutes before any media outlet.
[Notigroup Newsroom in collaboration with other media outlets, with information from the following sources]
