Schlapp, whose group is perhaps known best for its popular annual Conservative Political Action Conference, made his comments in an interview with The Washington Post and the Hill on C-SPAN's "Newsmakers." Trump has spoken at CPAC in recent years.
In announcing his presidential campaign last month, Trump made remarks about Mexican immigrants that have drawn criticism from Latino groups and prompted some of his corporate partners to sever ties with him.
“They’re bringing drugs,” Trump said. “They’re bringing crime. They’re rapists.”
Schlapp said that while the "tone and the words he chose are different from what I would choose," he understood the point Trump was trying to make.
"I actually heard on the radio today him saying what he was talking about is illegal immigrants. And that's an incredibly important distinction to draw," said Schlapp, adding: "When you have a broken immigration system, it's hard to characterize the nature of the illegal immigrants that come into our country."
Trump, who has surged into the top tier of the crowded GOP field in recent polls, "resonates with a lot of Americans," said Schlapp.
"It's undeniable that what he is saying is working out there in the country," he added.