US President Donald Trump has blamed the sharp decline in the American stock market on the electoral gains recorded by the opposition Democratic Party in the midterm elections earlier this week.

Trump made the accusation on Thursday in a post on his Truth Social platform following a major selloff in US equities.

“The Stock Market crashed today because the Dumocrats had a big Tuesday — So sad to see, you only have yourselves to blame!” he wrote.

However, market analysts attributed the decline largely to concerns that Democratic victories could threaten investments in artificial intelligence data centres, amid growing opposition to such projects across the United States.

The technology-focused Nasdaq recorded its worst single-day percentage decline since April 2025.

Data centre developments have faced opposition from voters across party lines, with several candidates who won seats in the midterm elections pledging to restrict or slow down their construction.

The Democrats made significant gains, flipping seats previously held by Republicans in South Carolina, North Carolina, Iowa, Kansas, Ohio, Texas and Maine.

In Maine, former logger Troy Jackson defeated longtime Republican Senator Susan Collins, securing the party’s seventh Senate seat captured from Republicans.

In Kansas, Methodist minister Adam Hamilton became the first Democrat elected to the Senate from the traditionally conservative state since 1932, while Iowa elected a Democratic senator for the first time since 2008.

In Texas, Democrat Talarico declared that he had defeated “Goliath” after winning a Senate seat, while Gina Hinojosa unseated Republican Governor Greg Abbott, ending decades of Republican control of the governorship.

The Democrats also retained key Senate seats, including that of Jon Ossoff in Georgia, as well as an open seat in New Hampshire.

Their gains extended to Michigan, where Abdul El-Sayed defeated former Republican lawmaker Mike Rogers, becoming the first Muslim elected to the upper chamber of Congress.

In the House of Representatives, Democrats made gains across Pennsylvania, Kentucky, Arizona, North Carolina, Wisconsin and New Jersey, including in districts Trump had won comfortably in the 2024 presidential election.

In one closely watched contest in Indiana, Democrat J.D. Ford defeated Republican Congresswoman Victoria Spartz in a district Trump had carried by 17 percentage points in 2024.

The Democrats also won Georgia’s governorship, with former Atlanta Mayor Keisha Lance Bottoms becoming the state’s first Black woman governor.

Republicans, however, recorded victories in Florida, where Trump-backed Byron Donalds became the state’s first Black governor, while Ashley Moody retained a Senate seat after overcoming a strong Democratic challenge.