For a fourth straight week the artificial intelligence trade lost ground, and this time the blow came from the ballot box.

Democrats won both chambers of Congress in Tuesday’s midterm elections. Several of the winners, including Texas Governor-elect Gina Hinojosa, had campaigned on pausing new data center construction.

Wall Street cheered first. The Dow Jones Industrial Average jumped 3% on Wednesday as Brent crude fell about 9% on bets that the result lowers the odds of renewed fighting with Iran.

Then investors did the math on AI. The Nasdaq 100 sank 6.4% on Thursday, its worst day since March 2020, and the S&P 500 lost 4.4%, its steepest drop since April 2025. The Philadelphia Semiconductor Index fell 12%.

Roughly $3 trillion in market value was erased from the S&P 500 in a single session, with Nvidia Corp. (NASDAQ:NVDA) alone shedding about $450 billion.

The year’s highest-flying memory stocks were hit hardest. SanDisk Corp. (NASDAQ:SNDK) plunged 22% and Micron Technology Inc. (NASDAQ:MU) 17%, though both still rank among the S&P 500’s four best performers of 2026.

Thursday’s close left the Nasdaq 100 nearly 15% below its Oct. 6 record. Even with a rebound on Friday, the index was down about 4.5% for the week in afternoon trading, on track for its longest weekly losing streak since March.

Friday’s jobs report complicated the picture. Employers added 165,000 jobs in October, against 65,000 expected, and the unemployment rate slipped to 4.1% from 4.2%. The prior two months were revised up by a combined 84,000.

Traders now price in about an 80% chance of a Federal Reserve rate hike in December, up from roughly 70% before the report.

The 10-year Treasury yield closed at 4.84% on Thursday, its lowest since early September, as investors sought safety. It rebounded to 4.86% after the jobs data, with the 2-year at 4.52% and the 30-year at 5.26%.

Michigan Sentiment Rises, AI Worries Surface

The University of Michigan’s preliminary November consumer sentiment index rose to 51.0 from 48.0, well above forecasts. Year-ahead inflation expectations fell to 4.3% from 4.7%, the lowest since August.

Survey director Joanne Hsu said consumers’ comments “revealed growing anxiety over a possible AI bubble.” Sentiment fell 5% among those with the largest stock portfolios.

“Despite this month’s improvement, sentiment is down 10% from February,” Hsu said.

Detroit’s two largest automakers held up better than Silicon Valley. General Motors Co. (NYSE:GM) touched a record $93.70 on Wednesday before the selloff erased its weekly gain.

Ford Motor Co. (NYSE:F) rose about 2% for the week, even as October U.S. sales slipped 0.8% to 174,123 vehicles and electric-vehicle sales fell 71%.