ESTERO, FLA. — Donald Trump roused thousands at a rally Monday in this Gulf Coast town with a promise to beef up border security to stem the threat of terror to the United States.

His vow took on new light in the wake of attacks in New York, New Jersey and Minnesota.

“Immigration security is national security,” the Republican presidential nominee said to roars of approval at Germain Arena near Fort Myers, Florida. “My opponent has the most open borders policy of anyone to seek the presidency.”

Trump applauded law enforcement officials for the arrest of the suspect behind Saturday’s bomb in Chelsea that injured 29.

“Today, we have caught this evil thug who planted the bombs,” the real estate mogul said before lamenting that Ahmad Khan Rahami would likely receive quality medical care and legal representation.

Trump ticked off recent instances of terrorism in San Bernadino, California, Orlando, and Paris and Nice in France.

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“We cannot let this evil continue,” he said of “radical Islamic terrorism,” though he did not reference his platform to temporarily ban Muslims from the country.

He called for “extreme screening” of those coming to the United States, saying people admitted into the country must love the country.

He blamed Hillary Clinton, the Democratic presidential nominee and former secretary of state, and President Barack Obama for policies that he said led to the spread of the Islamic State group.

Trump vowed to win Florida, a diverse battleground state that he was visiting for the second time in four days.

A Siena College Research poll released Monday showed Clinton with 41 percent support compared to Trump with 40 percent in a hypothetical four-way race in the Sunshine State with third-party candidates Gary Johnson and Jill Stein.

Clinton appears to be struggling to overcome Trump despite outspending him here on ads and campaign offices. She was to discuss the economy at an event Wednesday in Orlando.

Trump and Clinton — who spoke to millennials in Philadelphia on Monday — were on the stump in swing states with their first debate at Hofstra University one week away and Election Day just seven weeks away.

Trump supporters filled the Germain Arena’s 7,000-plus seats, and thousands packed the floor of the facility typically used for hockey games. Crowds were turned away at the door for lack of space.

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Many wore shirts that played off Clinton’s comment that half of her rival’s supporters can be placed into a “basket of deplorables,” flipping the insult into a badge of honor.

“I’m one of Trump’s adorable deplorables,” two women’s shirts read.

“Deplorable lives matter,” another woman’s shirt read.

State Rep. Dane Eagle (R-Cape Coral), a warm-up speaker, greeted Trump fans as “my fellow deplorables.”

Former Copiague resident and retired NYPD detective Larry Schwartz, 70, waited more than three hours in the sweltering humidity to see Trump.

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“I’m here because I can’t vote for Hillary. I won’t vote for Hillary,” said Schwartz, who now lives in Stonybrook, Florida. “All the lying, she doesn’t tell the truth.”

Schwartz, who said he was formerly a Democrat, said he was drawn to Trump as the law-and-order candidate.

“Blue lives matter,” he said, adding that Trump was a refreshing type of candidate: “It’s time to give someone a chance who doesn’t have political experience.”