While DeSantis rarely alluded to the former president during remarks at an evening rally, he showed less restraint afterward when taking questions from the media.

DeSantis bashed Trump on issues such as immigration, COVID policy and federal spending, suggesting that he had drifted away from conservative principles as president.

"Unfortunately, he's decided to move left on some of these issues," DeSantis said.

Trump, the front-runner in the Republican race, recently assailed DeSantis' handling of the COVID pandemic, when DeSantis resisted federal mask and vaccine mandates.

DeSantis called Trump's criticisms "detached from reality" and argued Republicans would respond by supporting him.

"I think he's doing it in a way that the voters are going to side with me," DeSantis said.

"Hell," he added, "his whole family moved to Florida under my governorship."

Trump has been a Florida resident since leaving office and several of his children live in the state.

Trump has repeatedly denigrated DeSantis' record and has argued that he has the best chance of defeating President Joe Biden in next year's election.

"Ron DeSantis is not a serious person who can take on Joe Biden and bring about the Great American Comeback," Trump campaign spokesman Steven Cheung said in response to DeSantis' remarks.

DeSantis' comments came after his first in-person event of his just-launched campaign.

He told a crowd packed inside a church in western Des Moines that the nation was "going in the wrong direction."

"We can see it," DeSantis said, "and we can feel it."

DeSantis, who launched his campaign in a glitch-plagued virtual forum on Twitter last week, has now turned to old-school politicking, beginning with two days in Iowa and then on to New Hampshire and South Carolina on a tour that will be closely watched to see if the buttoned-down, policy-minded governor can flash interpersonal skills that some critics have said he lacks.

Trump will be right behind him. He will hold events in Iowa the day DeSantis stumps in New Hampshire, a sign the battle for the nomination is about to enter a more intense phase.

Iowa is a key state for DeSantis. The Iowa caucuses next February will be the first nominating contest in the nation, and the state's sizeable white, evangelical Christian population has sometimes been at odds with Trump.

Trump lost the caucuses in 2016 to U.S. Senator Ted Cruz, who was able to attract much of the Christian vote. It was little surprise, then, that DeSantis held his initial Iowa event in the auditorium of an evangelical church.

DeSantis told reporters he expected to win a large share of the evangelical vote.

"I have a record of standing for what is right, and I'm willing to take arrows for that," he said.

DeSantis was introduced by Iowa's Republican governor, Kim Reynolds, and was joined by his wife, Casey DeSantis.

"I have a hunch they're going to be here a lot," Reynolds said.

DeSantis will hold four campaign events across the state on Wednesday as he looks to introduce himself to Iowa voters who are notorious for wanting to see candidates close-up before they attend the caucuses for picking party nominees.

Todd Jacklin of Johnston, Iowa, 62, was volunteering for the event, but that did not mean he was sold on DeSantis. He was there to listen, he said.

"I'm going to keep things open until next February," he said.

The nascent DeSantis campaign has been buttressed by a well-funded Super PAC, Never Back Down, which has taken on many of the day-to-day responsibilities of a presidential effort. At the Tuesday rally, workers for the group were asking attendees to support DeSantis in next year's caucuses.

Also in attendance were members of Moms for Liberty, a national conservative advocacy group that opposes liberal education polices and whose efforts in Florida have been strongly supported by DeSantis.