Ms. Stansbury, a water resources expert, previously worked on the Senate Committee on Energy and Natural Resources and served in the Office of Management and Budget under President Barack Obama. Mr. Moores, a former University of New Mexico soccer player, owns a health care business with his wife.

The Democrats’ victory on Tuesday night gives House Speaker Nancy Pelosi (D., Calif.) A little more leeway in legislative battles. Once Ms Stansbury is sworn in, Democrats could lose four votes from their own ranks on legislation opposed by all Republicans.

Politicians and analysts were eager to exploit the results for any early indication of the political climate under Mr Biden as both parties begin to prepare for next year’s midterm elections.

Ms Stansbury got 60.3% of the vote, compared to Mr Moores’ 35.7%, with 99% of constituencies reporting, according to the AP.

Republicans have slammed Ms Stansbury over crime issues and have proposed changes to police laws, campaign attacks likely to feature prominently in next year’s midterm elections. House Republicans unexpectedly won seats in the 2020 election, which many in the GOP attribute to the Democrats’ connection to calls by some liberals to fund police, following nationwide protests against police misconduct.

Mr Moores worked to tie Ms Stansbury to legislation she supported known as the Breathe Act, which would divert federal funding from federal police services and detention facilities and establish a new federal agency dedicated to security public. An advertisement from Mr Moores’ campaign accused Ms Stansbury of supporting America’s most dangerous legislation and said she was funding and dismantling police as homicides in Albuquerque increased.

There have been 48 homicides through May 23, according to crime statistics released by the Albuquerque Police Department. There were 24 in the first five months of last year and 76 for all of 2020.

In an interview with local television station KOB 4, Ms Stansbury said she wanted to address public concerns about crime by tackling economic and public health issues.

“When you talk to public safety officials, what they say is that the vast majority of crimes in Albuquerque are drug addiction related,” she said. “Over the past few decades, our behavioral health system has really collapsed.”

Regarding the Breathe Act, a spokeswoman for Ms Stansbury said on Tuesday that if the final legislation includes articles she cannot support, she will seek other solutions.

Police continue to divide House Democrats, some of whom have said last year’s GOP attacks on police funding were successful. In late May, House Democrats barely managed to pass a $ 1.9 billion additional spending bill to fund security on Capitol Hill when six Progressive Democrats refused to back it, opposing it. increased police funding without addressing what they saw as the main drivers of January 6. Attack on the Capitol: violent white supremacy, radicalization and disinformation.

Democrats had been largely favored to retain control of the seat in a district which Mr Biden won by 23 percentage points and where Mrs Haaland was re-elected last year by 16 points. No Republican has held the seat for more than a decade. Republicans have not made a significant investment in Mr. Moores’ campaign, according to a GOP official.

Republicans see the resumption of House control as within their grasp next year, bolstered by historical trends that favor the out-of-power party in a midterm election, as well as increased GOP control in the once-a-decade redistribution process that will establish new boundaries for House seats.

—Lindsay Wise contributed to this article.

Write to Kristina Peterson at [email protected]