With a late boost from President Trump, Ms. Hyde-Smith weathered criticism of her rhetorical gaffes and increased the Republican advantage in the Senate to 53-47.
JACKSON, Miss. — Senator Cindy Hyde-Smith, a Mississippi Republican who had to apologize for a cavalier reference to a public hanging, won a special runoff election on Tuesday, defeating the Democratic nominee, Mike Espy, who was trying become the state’s first black senator since Reconstruction.
Ms. Hyde-Smith’s victory, reported by The Associated Press, came in the final Senate race of the midterm elections and will set the Republican majority in the chamber at 53 to 47 once the new Congress is sworn in, a net pickup of two seats.
Teetering after several rhetorical gaffes drew a harsh spotlight to her campaign, Ms. Hyde-Smith received a last-minute boost from President Trump, who appeared at two rallies with her on Monday and cautioned Mississippians that a victory for Mr. Espy would also be one for Democratic leaders like Chuck Schumer and Nancy Pelosi.
The Republican win came as a deep relief to the party and Mr. Trump in a state where they typically never have problems in Senate races. Mr. Trump boasted repeatedly this year about his influence in helping his preferred candidates win elections, but the party had to go to unusual lengths — with the rallies, multiple tweets by the president, a vast financial investment and dozens of Republican election workers dispatched to the state — to help Ms. Hyde-Smith over the finish line.
Her victory is clearly good news for Senate Republicans, who will now have an expanded, conservative majority to help advance Mr. Trump’s judicial nominees and negotiate with a Democratic-led House.
Mr. Espy was the third prominent black Democrat to go down to defeat in a statewide race in the South this year, following losses by two gubernatorial candidates, Stacey Abrams in Georgia and Andrew Gillum in Florida.
Addressing supporters at the Mississippi Civil Rights Museum here less than three hours after the polls closed, Mr. Espy said he had already conceded to Ms. Hyde-Smith. “She has my prayers as she goes to Washington to unite a very divided Mississippi,” he said.
Ms. Hyde-Smith’s election reinforced Republicans’ grip on power in Mississippi, a state they have come to dominate since the early 2000s, and showed that the political realignments taking shape in parts of the South are still in a nascent stage in Mississippi.
Still, the fact that Ms. Hyde-Smith faced a challenging runoff election, after no candidate received a majority of the vote on Nov. 6, suggested that Democrats could make select races competitive once again. And the frantic efforts to salvage her seat signaled that rhetoric seemingly steeped in Mississippi’s racist past risks a modern political price.
Although Ms. Hyde-Smith was never on a glide path to power — she faced a Republican rival and Mr. Espy in the first round of voting, all but guaranteeing Tuesday’s runoff vote — her campaign became more seriously imperiled through her own statements, including one in which she said that if a supporter invited her to “a public hanging, I’d be on the front row.
