A Trump victory is "beginning to build," Gingrich added.
Gingrich was reacting to the Democratic Convention, saying that when the GOP gathers this week at the Republican Convention, the party needs only to continue pointing out their differences from Democrats in order to bolster Trump's chances.
"We don't have to want to make stuff up. We don't have to invent some post office phony scandal. We just have to tell the truth about how radical these people are," Gingrich said.
"We just have to tell the truth about how radical these people are."
The former speaker pointed to continuing chaos in places like Chicago, Seattle and Portland, Ore. -- large American cities run by Democrats.
"Rioting every day for 90 days, that begins to be a fact. And it was very interesting to me that neither [Joe] Biden nor [Kamala] Harris was willing to say a word about Antifa, [not] a word about a level of crime."
"You know, [we] have the mayor of Chicago announcing that she's going to have police on her own personal street because she wants her family to be safe. But good luck to the rest of the city," Gingrich added. "Well, I think this stuff sinks in at a level of reality that even NBC News can't cover up."
"The mayor of Chicago ... wants her family to be safe. But good luck to the rest of the city."
The Fox News contributor also blasted the Democratic presidential ticket and their chances of winning.
He called vice presidential candidate Harris "the most radical member of the Senate based on voting, which means she's to the left of [Bernie] Sanders and the left of Elizabeth Warren. I mean, you know how hard that is," Gingrich said. "Second, she's a terrible performer."
Gingrich added that Biden, the Democratic presidential nominee, gave the best speech of his career during the convention but believes Biden's position in the polls "is not going to last."
"I say to myself, when people get to know them better, just as happened with George McGovern in 1972, they're going to say, 'You know, ... I don't think so. I just I can't vote for you.'"