Global stocks slide after Democratic midterm wins in America stoke investor fears for the AI boom

From the Newshound archive · first published 4 November 2026.

Tech stocks led a broad global sell-off on Wednesday after Democrats swept both chambers of Congress in the US midterm elections, triggering alarm that AI-friendly Republican policies on regulation and energy could now be reversed. Investors fear a Democratic-controlled Congress will block or roll back Trump's agenda on data-centre permitting, power grid expansion and chip export rules that had underpinned the AI rally.

Prediction markets had flagged the swing, with Kalshi giving Democrats a 76% chance of taking both chambers by election day.

The Republican Party's odds of holding the House had collapsed to just 6%, their lowest since July 2025, according to Polymarket bettors.

Democrats' chances of a congressional sweep had stood at just 28% in January, making Tuesday's result a dramatic reversal for markets that had priced in continued GOP dominance.