The New Mexico Supreme Court is considering a GOP challenge to the congressional map and swing district boundaries

The Republican Party urged the New Mexico Supreme Court on Monday to throw out a congressional map that divided a politically conservative oil-producing region into multiple districts as part of a reshaping of a swing district along the U.S. border with Mexico.

The Supreme Court heard oral arguments without ruling Monday on the congressional map from the state’s Democratic lawmakers. Democrats say a swing congressional district in southern New Mexico remains competitive, even with the Republican incumbent ousted in last year’s election.

The Supreme Court’s ruling could affect the party representing the state’s 2nd Congressional District, where Democratic U.S. Rep. Gabe Vasquez is seeking a second term.

The district is one of about a dozen in the national spotlight as Republicans campaign to maintain their razor-thin majority in the U.S. House of Representatives in 2024. Courts recently ruled in Alabama and Florida that Republican-led legislatures have unfairly diluted residents’ voting power Black people. Legal challenges also continue for congressional districts in Arkansas, Kentucky, Louisiana, South Carolina, Tennessee, Texas and Utah.

A New Mexico district judge ruled in October that Democratic state lawmakers significantly diluted their political opponents’ votes, but the changes did not amount to “egregious” gerrymandering.

In an appeal of that ruling, the GOP said its large political minority in New Mexico would likely be excluded from representation in Congress for the entire decade before the maps are redrawn again. As evidence, the GOP cited incumbent Republican Congresswoman Yvette Herrell’s 2022 defeat by a former city councilwoman from Las Cruces.

“It is clear that Herrell was an incumbent who ran on the ballot several times with a very high ID and lost at the end of the day,” Harrison told the justices on Monday. “So it’s a very favorable year for Republicans, with an incumbent.”

The justices expressed skepticism, noting that Herrell lost by a slim margin of 0.7% in 2022 and also previously lost an open race for the seat in 2018 before the district was redrawn — indicators that the district was competitive and might remain so.

“The actual election results are what I have a problem with,” Judge Briana Zamora said.

Sara Sanchez, who represents Democratic legislative leaders, said the evidence in the case does not support allegations of egregious gerrymandering that would entrench one party in power or deprive voters of meaningful participation.

“Every map will favor one party over the other in any given district,” she said. “But dilution only becomes a constitutional harm when it rises to the level of giving effect to that entrenchment, and there was no evidence of that here.”

Democrats hold every statewide elected office in New Mexico, along with its three congressional seats and two Senate seats.