Nikki Haley, who was the first prominent Republican to announce a challenge to former President Donald J. Trump in the 2024 race, has yet to see her presidential campaign catch fire. On Sunday night, she had a fresh opportunity to make the case for her candidacy during a 90-minute CNN town hall in prime time, in an effort to emerge from the low single digits in polls where she has been mired.

Ms. Haley, the former governor of South Carolina and United Nations ambassador under Mr. Trump, was well versed on policy issues, consistently upbeat and evenly tempered. Although she drew contrasts with Mr. Trump, she dodged opportunities to make him — or even President Biden — into a political punching bag.

At the end of the night, an audience member praised her demeanor as “a breath of fresh air,” earning applause from the house full of Iowa Republicans. But that also meant that there were few shoot-out-the-lights moments that could win Ms. Haley headlines and a new look from primary voters, who now face a growing field of Republicans who are in — or soon to enter — the race.

Here are some takeaways from the event on Sunday night.

Compared with CNN’s explosive, much-criticized town-hall-style event with Mr. Trump last month, this one was a throwback to earlier, less combative times. There was no torrent of fact-checking, no audience jeers whipped up from the stage and no forceful interrogation of the candidate. Jake Tapper, the anchor who moderated, never found the need to correct Ms. Haley.

The two big red elephants in the room, Mr. Trump and Gov. Ron DeSantis of Florida, were mostly mentioned indirectly, but those two Republican presidential contenders were present nonetheless. Ms. Haley repeated her position that in order to save Social Security and Medicare, it would be necessary to raise the retirement age for young workers and to limit benefits for the wealthy. Both Mr. Trump and Mr. DeSantis, who once supported similar changes, now say they won’t touch the programs.

“I think it’s important to be honest with the American people,” Ms. Haley said. “We are in this situation. Don’t lie to them and say, ‘Oh, we don’t have to deal with entitlement reform.’ Yes, we do.”

Ms. Haley also criticized Mr. DeSantis for his attacks on Disney as a “woke” company. She had no beef with the Florida governor’s criticism of Disney’s opposition to what critics call his “Don’t Say Gay” law, and even said she would have gone further than that law to prevent talk of gender and sexuality in schools. But she called Mr. DeSantis “hypocritical” for accepting tens of thousands of dollars in political contributions from Disney before turning on the company, and for using taxpayer dollars to sue it. “Pick up the phone deal with it,” she said. “Settle it the way you should, and I just think he’s being hypocritical.”

On social issues including abortion, gun restrictions and transgender rights, which animate much of the Republican voting base, Ms. Haley toed a conservative line. She defended, for example, leading the U.S. withdrawal from the Paris climate accord while at the United Nations. (President Biden rejoined the accord in 2021.) But she displayed less of the punitive rhetoric on the issues that Mr. Trump and Mr. DeSantis have made crucial to their messages.

Ms. Haley deflected on whether she supported a federal six-week abortion ban such as the one her home state of South Carolina recently passed. Any national restrictions, she said, would require 60 senators to approve, which she said was so remote that the question barely merited consideration.

In the most stirring moment of the night, Ms. Haley described persuading reluctant Republican lawmakers in South Carolina to remove the Confederate battle flag from the State Capitol after the massacre by a white supremacist of Black worshipers at the Mother Emanuel church in Charleston in 2015.

She agreed with barring transgender girls from school sports and even seemed to suggest that allowing “biological boys” in girls’ locker rooms was connected with the high rate of teenage girls who have considered suicide.

At the same time, she acknowledged that “we do need to be humane” about transgender children. In South Carolina schools when she was governor, Ms. Haley said, principals made private bathroom accommodations for them. “They were safe, and the majority of the student body didn’t even have to deal with it,” she said.

Ms. Haley also carved out differences with Mr. Trump and Mr. DeSantis on foreign policy issues, as she has in the past. The former U.N. ambassador disputed Mr. DeSantis, who has called Russia’s invasion of Ukraine a “territorial dispute” — a characterization he has since walked back — and she dismissed Mr. Trump’s refusal to say whether Ukraine should win the war.

She said both positions represented a naïve trust in Russia’s president, Vladimir V. Putin. “If Ukraine pulls out,” Ms. Haley said, “then we’re all looking at a world war.”

Asked by Mr. Tapper about Mr. Trump’s congratulating North Korea’s leader, Kim Jong-un, for recently ascending to a leadership role in the World Health Organization, Ms. Haley called Mr. Kim, whose flattering letters Mr. Trump once praised, a “thug.”

“There is no reason we should ever congratulate the fact that they are now vice chair of the World Health Organization,” Ms. Haley said.