The Block: $622,608 Michigan bet fits trader’s wider pattern

The Block compared the trader’s Michigan bets to 15 other Senate races dating back to mid-September.

The hit

Vanderbilt researchers flagged a Polymarket trader’s profitable Senate bets, placed before Times/Siena polls dropped in Nebraska & Michigan, as potentially suspicious, the New York Times reported on Friday. The Block’s analysis of onchain records found the account, dubdubdub2, has a long history of large speculative trades & DeFi activity, & may have placed a $153,000 Kalshi bet on Nebraska after the poll was already public.

Why it matters

For bettors, it’s a reminder that big, well-timed wins on prediction markets don’t automatically mean foul play. Two experts told The Block the trader’s pattern looks more like a crypto whale making large directional bets than someone exploiting leaked polling data, though they said foul play can’t be definitively ruled out. One of them, Rajiv Sethi of Barnard College, said the bets looked like wagers on the eventual outcomes rather than an attempt to profit from the Times/Siena polls, adding the trader may have used non-public information such as privately commissioned surveys instead.

The record

Nebraska bet	$191,277 on Pete Ricketts’ re-election, netting over $77,000 (New York Times)
Michigan bet	$622,608 on a Democratic win, netting over $180,000 (New York Times)
Michigan daily total	largest single-account daily total across 16 Senate races The Block analysed back to mid-September, nearly 3x the next biggest (The Block)
Kansas market reaction	odds jumped from about 52.5% to 60.5% within 30 minutes, the biggest move of the Nov 1 polls (The Block)
Trader’s Kansas exposure	zero bets placed, in a smaller market: $1.9m traded there versus $7.9m in Michigan (The Block)

What happens next

Polymarket told the New York Times it is conducting its own investigation into the trades.

Sources: Onchain data casts doubt on insider-trading theory in NYT’s ‘suspicious’ election betting story

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