State Representative Matt Morgan (R-TX) holds a map of the new proposed congressional districts in Texas, during a legislative session as Democratic lawmakers, who left the state to deny Republicans the opportunity to redraw the state's 38 congressional districts, begin returning to the Texas State Capitol in Austin, Texas, U.S. August 20, 2025. REUTERS/Sergio Flores/File Photo

By Joseph Ax

WASHINGTON (Reuters) -A Utah judge has thrown out a new U.S. congressional map passed by the Republican-led legislature in favor of an alternative that appears likely to result in flipping one of the state’s four U.S. House seats to Democrats in next year’s midterms.

In a decision late on Monday night, District Judge Dianna Gibson called the legislative map an "extreme partisan outlier" that illegally gave Republicans an advantage. The Republican-drawn plan split Salt Lake County, where most of the state’s Democrats reside, in half.

Gibson chose one of two alternative maps proposed by voting rights groups that had sued over the map, both of which created a Democratic-leaning district centered on Salt Lake County.

Her decision arrived amid a national battle over redistricting that began when Texas, acting at President Donald Trump’s behest, redrew its congressional map to take aim at flipping five Democratic seats. In response, California voters last week overwhelmingly approved a new map in that state that targets five Republican incumbents.

Other Republican- and Democratic-led states have also either drawn new maps or are considering doing so. While manipulating district lines to benefit one party, known as gerrymandering, is not new, redistricting typically only takes place once a decade, when states are constitutionally mandated to redistrict based on the decennial U.S. Census.

In 2026, Democrats need to flip only three seats won by Republicans last year to take control of the U.S. House.

In Utah, Gibson had ordered lawmakers in August to draw a new map after finding that Republicans illegally repealed a voter-approved referendum that created an independent redistricting commission.

But she agreed on Monday with voting rights groups that the resulting Republican-backed plan remained too gerrymandered to stand.

"Based on the evidence presented, the Court finds that Map C was drawn with the purpose to favor Republicans," she wrote.

Republican state lawmaker Candice Pierucci, who helped lead the legislature's map drawing, called the decision "a clear example of judicial activism" on X.

Democratic U.S. Representative Suzan DelBene, the chair of the party's national congressional campaign arm, said in a statement, "This ruling is a victory for every Utahn who believes voters – not politicians – should decide who their representatives are."

(Reporting by Joseph Ax; editing by Susan Heavey and Alex Richardson)