WASHINGTON (AP) — Ron DeSantis plans to kick off his presidential campaign in Iowa on Tuesday, the start of a busy week that will take him to 12 cities in three states as he tests his pitch as the most formidable Republican challenger to former President Donald Trump.

The Florida governor's two-day trip to the leadoff caucus state — starting at a suburban Des Moines megachurch and ending at a Cedar Rapids racetrack — comes after a stumbling online announcement last week that formalized his long-anticipated entry into the growing Republican field. It will be followed by stops in early primary states New Hampshire and South Carolina.

DeSantis' scheduled Tuesday evening stop at Eternity Church in Clive is a conspicuous nod to the evangelical Christians who wield outsize influence in Iowa's Republican presidential caucuses. His visit will give voters an opportunity to meet the new candidate just as he has been stepping up his criticism of Trump.

"He's got a big hill to climb — and I think everybody would agree with that — to be able to convince people that he can overcome Trump, that he can do a job as good as, if not better than, Trump," said Bernie Hayes, the Republican chair in Linn County where DeSantis plans to wrap up his Iowa jaunt Wednesday.

DeSantis, assailed by Trump for months, pivoted from oblique swipes to direct questioning of the former president's conservative credentials during a round of interviews with friendly media last week, notably his handling of the coronavirus pandemic and his record on criminal justice.

DeSantis called a bipartisan bill Trump signed in 2018 that reduced mandatory minimum federal prison sentences and allows a pathway for non-violent offenders to reduce prison time "a jailbreak bill." As a member of Congress, DeSantis voted for an early version of the measure but had left Congress after he was elected governor and before the final, less strict bill passed.

DeSantis also said Trump wrongly "turned the country over to Fauci," referring to Anthony Fauci, the former director of the National Institute of Allergy and Infectious Diseases who helped lead the country's COVID-19 pandemic response.

DeSantis announced his campaign May 24 during an online conversation with Twitter CEO Elon Musk. The audio stream crashed repeatedly, making it difficult for most users to hear the announcement in real time, a stumble campaign officials and others quickly dismissed as a minor setback.

DeSantis was undeterred in laying out his message, that conservative legislative victories this year in Florida, chiefly on cultural topics such as restricting sexual orientation discussion in schools, are the antidote for what he calls a nation controlled increasingly by the extreme left. He also has gone after Disney, seeking to strip the state's entertainment giant of its self-governing authority for opposing the state law that critics have dubbed the "Don't Say Gay" law.

"American decline is not inevitable — it is a choice," DeSantis said during the glitchy audio stream. "And we should choose a new direction — a path that will lead to American revitalization."

DeSantis has a running start in Iowa and other early voting states, thanks to Never Back Down, a super political action committee that is using money the group can receive in unlimited sums from wealthy contributors to begin organizing support for him. Campaign finance law requires the group to do its work without coordinating with DeSantis.

Iowans should see staff and volunteers for the group working the perimeter of DeSantis' church event in Clive on Tuesday, as well as events Wednesday in conservative western Iowa's Sioux City and Council Bluffs and the manufacturing and college city of Pella in east-central Iowa before the finale in Cedar Rapids. By making his bid official, DeSantis gives the group a rallying figure whose events it can attend, even if cannot coordinate with DeSantis' official campaign group.

The tack, untested and not without risks, is aimed at maximizing super PAC dollars. It's also a way of helping DeSantis race in Iowa to catch Trump, whose campaign says it has banked thousands of supporters thanks to a more disciplined, data-driven outreach effort than Trump's seat-of-the-pants 2016 campaign. That operation landed him in second place but with thousands of potential supporters left uncontacted by the campaign.

And Trump, besides his regular social media broadsides attacking DeSantis, has attempted to shadow him in Iowa to demonstrate his own popularity. In March, Trump headlined an event at a Davenport theater three days after DeSantis spoke to an audience and took questions from Iowa Gov. Kim Reynolds during the Florida governor's tour promoting his memoir.

Two weeks ago, Trump scheduled a rally in Des Moines to take place the same day DeSantis was headlining Iowa Republican events in western and eastern Iowa as the guest of Rep. Randy Feenstra and the state GOP. However, Trump scrubbed the outdoor event the day he was to arrive due to threats of severe weather.

Turning the tables on Trump, DeSantis swooped into Des Moines that evening for an impromptu appearance that helped his campaign create the desired impression of him dancing in the ring with the heavyweight.

Trump is scheduled to return to Iowa on Thursday, the day after DeSantis' tour, and is expected to hold events in the Des Moines area, meet influential conservatives and sit for an interview that evening with Fox News Channel host Sean Hannity.