Gov. Tate Reeves of Mississippi secured a second term, according to The Associated Press, fending off a vigorous challenge from Brandon Presley, a conservative Democrat whom he cast as a far-left acolyte of President Biden, and overcoming concerns about a shortage of excitement among conservatives.

Mr. Presley conceded to Mr. Reeves, a Republican, shortly before 11 p.m. Central time.

While the outcome was no surprise, given the Republican Party’s dominance in the state, it did not come quite as easily as some might have expected at the outset of the race. Mr. Presley, a little-known utilities regulator, mounted an energetic campaign that kept Mr. Reeves on his toes.

“This victory sure is sweet,” Mr. Reeves said on Tuesday night.

“This victory belongs to you,” he told supporters. “This victory is more than just who will occupy the governor’s mansion over the next four years. It’s really about the direction that our state will go over the next four years. Mississippi has momentum.”

Mr. Reeves, who was first elected governor in 2019, campaigned on his conservative credentials while constantly linking Mr. Presley to Mr. Biden and other national Democrats who are widely unpopular in Mississippi.

He boasted about tax cuts he had signed and promised to chase his unrealized ambition of eliminating the state’s income tax. Mr. Reeves also pointed to raises for teachers, which he signed into law last year and which were among the largest in state history, and to the fact that unemployment had dropped to its lowest rate in decades.

Mr. Presley traveled the state arguing for expanding Medicaid and slashing the state’s high grocery tax, which is one of the highest in the nation, saying he would bring relief to working-class families. He focused heavily on mobilizing Black voters, but he also believed that he could peel away white centrists and Republicans who were drawn to his message.

Mr. Presley, a second cousin of Elvis Presley and a former mayor of Nettleton, Miss., a town of about 2,000 in the northern part of the state, focused on his personal story of struggling through poverty as a child. He cast Mr. Reeves as disconnected from the experiences of the state’s working poor.

He also relentlessly needled Mr. Reeves for a sprawling scandal in which millions of dollars in federal welfare funds had been siphoned away from supporting the state’s poorest residents. The money was instead used for the pet projects of wealthy and connected individuals, including a volleyball stadium at the University of Southern Mississippi championed by Brett Favre, the former professional football player.

Mr. Reeves denied any involvement in the scandal, which, he noted, largely unfolded before he began his term as governor in 2020. (He had been lieutenant governor.) Still, he was criticized for his handling of the efforts to claw the money back, including his administration’s firing of a former federal prosecutor who had been hired to recoup those funds.

The Cook Political Report, a nonpartisan newsletter, recently found that the election had “morphed into a competitive fight.” It described Mr. Presley as an “unusually strong contender.”

But ultimately Mr. Presley failed to close the gap and thwart Mr. Reeves’s triumph, an outcome that underscores the strength the Republican Party has amassed in Mississippi.

“We left no stone unturned,” Mr. Presley told supporters on Tuesday night, describing the aggressive effort his campaign to crisscross the state, making stops in all 82 counties. He argued that the race had succeeded in bringing attention to urgent issues, like Medicaid expansion.

But as he conceded, he said that, however contentious the race had gotten, Mississippi had to move forward without being consumed by partisan divisions.

“This is bigger than one man,” Mr. Presley said. “We can lose this race tonight recognizing good on the other side.”