NATIONAL HARBOR, Md. — Sen. Rand Paul (R-Ky.) fired up conservative activists Friday with an address blasting the Obama administration for spying on American citizens.

Sen. Rand Paul, R-Ky., speaks at the Conservative Political Action Committee annual conference in National Harbor, Md., Friday, March 7, 2014. (AP/Susan Walsh)

“If you have a cellphone, you are under surveillance from the federal government,” Paul said at the annual Conservative Political Action Conference, held just outside Washington, D.C. “I believe what you do on your cellphone is none of their damned business!”

Paul’s line was met with thunderous applause and a chant of “President Paul! President Paul!”

The Kentucky senator focused much of his attention on what he characterized as Obama’s unconstitutional administration.

“Imagine a time when the White House is once again occupied by a friend of liberty,” he said. “You might think I’m talking about electing Republicans. I’m not. I’m talking about electing lovers of liberty.”

“It isn’t good enough to pick the lesser of two evils,” he said.

He said Americans must “stand and be heard” and fight for their rights.

Referring his recent class-action lawsuit against the National Security Agency, Paul warned of the dangers of a government that spies on its people.

“I believe this is a fundamental constitutional question: Can a single warrant be applied to millions of Americans?’ he asked.

The crowd roared: “No!”

“I took a stand,” he said. “I sued the president.”

He then asked a hypothetical: “How will history remember Barack Obama?”

There was a slight pause and then some in the audience started to laugh.

“I don’t question President Obama’s motives,” Paul said, “But history will record his timid defense of liberty.”

Paul reiterated his opposition to the government surveillance programs: “Mr. President, we will not let you run roughshod over our rights. We will challenge you in the courts. We will battle you at the ballot box. Mr. President, we will not let you shred our Constitution!”

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