France, Nov. 4 -- Strong wins for Democratic candidates threaten the prospects for energy-hungry data centres in key US states, and could slow the AI rollout that has driven Wall Street higher over the past four years.

The prospect of tighter regulation weighed on shares in AI heavyweights such as Elon Musk's SpaceX before the opening of US markets, after falls for major Asian chipmakers including South Korea's Samsung.

Growing concern

The campaign was marked by growing concern about the environmental impact of the data centres springing up across the United States. It ended in a stinging rebuke for President Donald Trump's Republican Party. Trump is an enthusiastic supporter of light-touch regulation for what he calls "super intellige...