PHILADELPHIA — Donald Trump was met with tears and gratitude as he sat with African-American supporters Friday, including the mother of a slain young woman who was killed by a man living in the United States illegally.

The back-to-back meetings, held in a ballroom in Northwest Philadelphia, underscored the balancing act the Republican nominee is playing as he tries to expand his support in the race against Democrat Hillary Clinton.

While Trump works to broaden his appeal among more moderate and minority voters, he is also working to maintain his popularity with his core GOP base by pressing his hard-line views on immigration.

At the invite-only roundtable discussion, Trump met with a dozen local business, civic, and religious leaders who praised him for coming to the city as part of his outreach efforts.

Trump was warmly received by the group, including Daphne Goggins, a local Republican official, who wiped away tears as she introduced herself to Trump, saying she has been a Republican for years but, ‘‘for the first time in my life, I feel like my vote is going to count.’’

Renee Amoore, a local business leader, assured Trump that he has support in the black community, despite his low standing in public opinion surveys.

‘‘We appreciate you and what you’ve done, coming to the hood, as people call it. That’s a big deal,’’ she said.

In a separate development Friday, the Commission on Pr esidential Debates announced that NBC News chief anchor Lester Holt will moderate the first of three scheduled debates between Clinton and Trump scheduled for Sept. 26.

The first and third debates will be question-and-answer sessions, with a journalist choosing the topics. The third session will be moderated by Chris Wallace of Fox News on Oct. 19.

ABC’s Martha Raddatz and CNN’s Anderson Cooper will team up for the second session on Oct. 9, a town hall-style meeting with half of the questions to be posed by audience members.

Each of the debates is scheduled for 90 minutes, with a 9 p.m. EDT start time.

The commission also said Elaine Quijano of CBS News will lead the vice presidential debate between Republican Mike Pence and Democrat Tim Kaine on Oct 4.

Trump’s meeting in Philadelphia also showed the challenges he faces making inroads with African-Americans and Latinos.

Protesters gathered in front of the building where he appeared, and a coalition of labor leaders met nearby to denounce Trump’s outreach to black voters as disingenuous and insulting.

Ryan Boyer of the Labor District Council said Trump ‘‘has no prescription’’ to help inner-city people. ‘‘He did nothing for African-Americans in 30 years of public life,’’ he said. “We reject his notion that we have nothing to lose by supporting him.’’

The next stop for Trump is Detroit on Saturday, where blacks make up some 83 percent of the population.