Peter Navarro, Trump's former White House trade adviser, was greeted with loud applause as he took to the stage hours after he was released from federal prison upon completing his sentence on contempt of Congress charges.

Navarro served four months in a low security facility in Miami for defying a subpoena from the Jan. 6. congressional committee.

"I've got a very simple message for you. If they can come for me, if they can come for Donald Trump -- be careful, they will come for you," he told the crowd.

"If we don't control our government, their government will control us," he continued.

Navarro said the "D.C. swamp" jailed him "but did not break me," as the crowd chanted "Fight, fight, fight."

"They will never break Donald Trump," he said.

Navarro called himself a "wake-up call," adding, "I went to prison so you don't have to."

Newt Gingrich, the former House speaker who ushered in "The Contract with America" conservatism, tried to square Trump's brand of Republicanism with Reagan's.

Trump "understands that when faced with multiple adversaries across the globe, the Reagan principle of peace through strength is the only road for safety in America for the American people," he said.

Gingrich's attack line: "We have to remember that the greatest threat to American safety is not Biden's brain. The greatest threat is Biden's policies, and the people he appoints to implement them."

–ABC's Jacob Steinberg

Florida Rep. Matt Gaetz took the stage and did not waste time laying into the Democrats and Biden over their policies.

He received loud applause from the crowd for his zingers that included a jab at New Jersey Sen. Bob Menedez, who was convicted this week on bribery charges.

"Under Biden-Harris, inflation has gotten so bad you can no longer bribe Democrat senators with cash alone," he said. "You have to use gold bars just so that it holds value."

The crowd also laughed when Gaetz claimed under Trump that there "were only two genders."

Gaetz is currently the subject of a House Ethics Committee investigation into alleged sexual misconduct allegations but did not mention the probe during his speech. He has denied all of the allegations.

Gaetz thanked the crowd for "having his back."

South Carolina Rep. Nancy Mace cited her military school education in backing Trump's candidacy.

"25 years ago, this high school dropout became the first woman to graduate from the Citadel, the Military College of South Carolina," she said.

Mace, the daughter of a brigadier general, said Trump will project military strength and "be prepared to take on the challenges of this historic moment," citing what she said was the threat from China.

Mace also told the convention she was a rape survivor and a single mom. "To women tonight who can relate," she said, "you have a friend and a sister in me. And I will fight like hell for you."

Mace has not always been in Trump's corner. Once a vocal critic, Mace had former South Carolina Gov. Nikki Haley's endorsement in 2022 and received financial contributions from PACs linked to top GOP leaders as she faced a primary opponent endorsed by the former president.

Since then, the roles have been reversed: Trump enthusiastically backed Mace after she endorsed him in the state's presidential primary over Haley, and McCarthy has sought revenge for Mace's vote to oust him from the speakership. Mace handedly won her primary.

-ABC's Brittany Shepherd and Chris Boccia