Republican Rep. Will Hurd will be re-elected in Texas' 23rd District, defeating Air Force veteran Gina Ortiz Jones, NBC News is projecting.
Health insurance was a major issue in the campaign in the relatively poor battleground district, where the median household income is below the national median and nearly 1 in 5 adults has no health insurance. That's more than twice the median for all congressional districts.
NBC News projected that Democrats would take control of the House.
Immigration was also a major issue in the heavily Hispanic district, which stretches along much of the Mexican border and is one of the most rural in the country.
The district is also a perennial battleground. Hillary Clinton won by 3.4 percentage points in 2016, but the district voted for Mitt Romney in 2012 and Barack Obama in 2008 by thin margins.
The candidates raised substantial campaign war chests of nearly $5 million each. The race also attracted more than $7 million in outside spending, about evenly divided between the two sides. Most of the money was spent on attack ads in the final days of the campaign.