Hillary Clinton cast the presidential election Monday as a moment of national reckoning — and rejection of Donald Trump as a national imperative.

“Just imagine Donald Trump in the Oval Office, facing a real crisis,” Clinton said. “What happens when somebody gets under his skin? I don’t know if the United States can afford that kind of risk.”

Campaigning in critical Florida, Clinton warned that voters should not be fooled by what she called an effort to refurbish the Republican nominee’s image.

“There is no other Donald Trump,” Clinton said. “What you see is what you get.”

It was Clinton’s second trip to Florida in a month, a mark of the state’s importance on several fronts this election. Long a swing state prized for 29 of the 270 electoral votes needed to win and a dependable source of Democratic campaign cash, Florida this year is also an important part of Clinton’s strategy to turn out large numbers of Latino voters.

Democratic presidential nominee Hillary Clinton vowed to help Puerto Rico address the island’s economic difficulties at a rally in Kissimmee, Fla., Aug. 8. (The Washington Post)

Clinton leads Trump in the state by 6 percentage points in a statewide poll conducted by Suffolk University last week. She held a similar lead in other state polling in July, before the Republican and Democratic conventions.

“He’s not only putting our national security at risk, now he’s putting our economy at risk,” Clinton charged.

[Former GOP national security officials: Trump would be ‘most reckless’ U.S. president in history]

She tweaked Trump for economic policies that she said would cost millions of jobs and business practices that she said have cheated small businesses.

“Florida would gain 650,000 jobs under my plan [and] lose more than 200,000 jobs under Trump,” Clinton claimed.

Trump’s economic policy speech Monday in Detroit was an effort to “make these old tired ideas sound new,” Clinton said.

“But here’s what we all know. His tax plan will give super big tax breaks to large corporations and the really wealthy,” she said. “He wants to roll back regulations on Wall Street; he wants to eliminate the Consumer Financial Protection Board, which has saved millions of dollars for Americans. He wants to basically just repackage trickle-down economics.”

To laughter from a crowd of more than 2,000 at the St. Petersburg Coliseum, Clinton invoked some old-fashioned folk wisdom.

“You know that old saying, ‘Fool me once, shame on you; fool me twice, shame on me?’ ” Clinton said playfully.

She also toured a family-run small brewery business in St. Petersburg and was rallying Democrats outside Orlando later Monday. The area is home to large numbers of Puerto Rican and Dominican immigrants atop other Hispanic populations drawn by tourism and agriculture.

Clinton said that as a senator from New York “I paid a lot of attention to Puerto Rico. We had a big Puerto Rican population in New York just like you do here in central Florida.”

And in both places, she noted, Puerto Ricans can vote for president. Although American citizens, Puerto Ricans cannot vote for president while living on the island, but can do so when living in the country proper.

“We want to register everyone to vote who is eligible to vote,” she told a crowd in Kissimmee.

On Tuesday, Clinton plans to tour a clinic in a neighborhood where the Zika virus has been detected.

“I will be visiting health professionals on the front lines in Miami, who are confronting the Zika challenge,” Clinton said. “Because Washington cannot keep ignoring the needs of the families of Florida.”

Clinton was introduced in St. Petersburg by Sen. Bill Nelson, who praised Senate colleague and vice presidential nominee Sen. Tim Kaine of Virginia, and called Clinton the clear choice in temperament and experience.

“Do you want somebody who will fly off the handle? Or do you want somebody who is steady?” Nelson asked. “Do you want somebody who has no idea about the subject that he is talking about, or do you want somebody who is really prepared?”

Clinton is holding fundraising events Tuesday in South Florida. It was not clear whether she will see Rep. Debbie Wasserman Schultz, a Clinton ally who was ousted last month as chairwoman of the Democratic National Committee.

Also Monday, the chief spokesman for the Florida Republican Party, who is Hispanic, said he is leaving his job and joining a conservative organization due to differences with GOP presidential nominee Donald Trump.

Wadi Gaitan, a former senior House Republican aide who focused on Hispanic affairs, becomes yet another high-profile Latino Republican official to leave his job because he can no longer tolerate defending and explaining Trump. The Republican nominee has spent much of the past year maligning immigrants, minorities and women, a strategy that helped him win the party’s nomination but that has led to historically poor approval ratings among black and Latino voters.

Gaitan will be joining the LIBRE Initiative, a grass-roots organization backed by the industrialists Charles and David Koch.

“I’m thankful for my almost two years with the Florida GOP, however, moving on gives me a great, new opportunity to continue promoting free market solutions while avoiding efforts that support Donald Trump,” Gaitan said in a statement.

The LIBRE Initiative and its executive director, Daniel Garza, remain active in Hispanic communities nationwide, spending millions of dollars in the past year trying to draw Latino voters to support conservative or libertarian policies. The group does not advocate for political candidates. Garza has said that Trump’s combative anti-immigrant rhetoric has made his organization’s outreach more difficult.

Ed O’Keefe in Washington contributed to this report.