The US Supreme Court revived on Thursday a redrawn Texas electoral map designed to add more Republicans to the US House of Representatives, boosting President Donald Trump's quest for his party to keep control of Congress in the 2026 midterm elections.

The justices granted a request by Texas officials to lift a lower court's ruling that had blocked the state from using the Trump-backed map, which could flip as many as five currently Democratic-held US House seats to Republicans.

The lower court concluded that the map likely was racially discriminatory in violation of US constitutional protections.

The court, which has a 6-3 conservative majority, issued its ruling in an unsigned order.

Its three liberal justices dissented.

Republicans currently hold slim majorities in both chambers of Congress.

Ceding control of either the House or Senate to the Democrats in the November 2026 elections would endanger Trump's legislative agenda and open the door to Democratic-led congressional investigations targeting the president.

"The District Court improperly inserted itself into an active primary campaign, causing much confusion and upsetting the delicate federal-state balance in elections," the Supreme Court said in a brief opinion explaining the decision.

The court in the order, acknowledging the political aims of Texas to benefit the Republican Party, also said the lower court mistakenly did not fault the new map's challengers for not themselves producing "a viable alternative map that met the state's avowedly partisan goals."

The Supreme Court's ruling comes amid a nationwide battle unfolding in Republican-governed and Democratic-led states involving the redrawing of electoral maps to change the population composition of congressional districts for partisan advantage.

Liberal Justice Elena Kagan criticised the court's majority, saying it disrespected the work of the lower court, whose ruling actually was authored by a judge appointed by Trump.

"We are a higher court than the district court, but we are not a better one when it comes to making such a fact-based decision," Kagan wrote in a dissent joined by Justices Sonia Sotomayor and Ketanji Brown Jackson.

"This court's stay guarantees that Texas's new map, with all its enhanced partisan advantage, will govern next year's elections for the House of Representatives.

And this court's stay ensures that many Texas citizens, for no good reason, will be placed in electoral districts because of their race.

And that result, as this court has pronounced year in and year out, is a violation of the Constitution," Kagan wrote.

Republican Texas Attorney Ken Paxton, responding to the court's ruling, said that "Texas is paving the way as we take our country back, district by district, state by state."

"This map reflects the political climate of our state and is a massive win for Texas and every conservative who is tired of watching the left try to upend the political system with bogus lawsuits," Paxton said. (Reuters)