 -- Sen. Rand Paul got a rousing reception this afternoon at the Conservative Political Action Conference, lighting up a crowd that tends to have a libertarian streak to it, saying, “In the coming weeks, I will propose the largest tax cut in American history.”

Speaking with rolled-up sleeves, he promised to pitch “a tax cut that will leave more money in the paychecks of every worker in America. My tax plan will keep the IRS out of your life and out the way of every job creator in America. My plan will also cut spending and balance the budget in just five years.”

Paul, R-Ky., blasted Congress, now controlled by Republicans, calling it “dysfunctional.”

“Often, bills are plopped on our desk with only a few hours to review,” he said. “No one, and I mean no one, is able to read what is in the bill. I propose something truly outrageous: Congress should read every bill.”

The crowd was packed with supporters, and Paul was interrupted by chants of “President Paul, President Paul.” He perhaps received the loudest applause when talking about personal privacy and going after the woman he may face if he they both choose to run in 2016: Hillary Clinton.

“Hillary’s war in Libya is a perfect example,” he told the CPAC crowd in National Harbor, Maryland. “Hillary’s war made us less safe," adding, "Libya's less stable."

He said to cheers: “It’s time for Hillary Clinton to permanently retire.”

Calling the crowd “lovers of liberty,” he asked them to “rise to the occasion.”

“You do have a right to privacy," he said. "Your rights are who you are, your rights are what you are, your rights are in your DNA -- and the government can, quite frankly, get over it.

"I say that the phone records of law-abiding citizens are none of their damn business," he added. "From within, our freedom is threatened by debt and by a government that regulates everything that moves.”

He differed in some ways with other Republican presidential contenders who have taken the stage at the conference since Thursday, specifically on the issue of foreign policy -- an issue that may make him an outlier in the GOP field, but was well-received by the libertarian-leaning activists gathered.

“At home, conservatives understand that the government is the problem, not the solution. But as conservatives, we should not succumb to the notion that government inept at home will somehow become successful abroad,” he said, "that a government that can’t even deliver the mail will somehow be able to create nations abroad. Without question, we must be strong. Without question, we must defend ourselves. I envision an America with a national defense unparalleled, undefeatable and unencumbered by nation building.”

He ended the speech by asking the crowd to “stand” with him: “Will you fight for freedom? Will you vote for freedom?”

Paul is popular with the CPAC crowd. He has won the CPAC straw poll the last two years, and his father, former Rep. Ron Paul, a three-time , won the straw poll in 2010 and 2011. This year's winner will be revealed Saturday.

However, Paul received some criticism today at CPAC, even if it was veiled.

Right after Paul spoke, former Sen. Rick Santorum, R-Pa., a 2012 presidential candidate, took the stage. Santorum didn’t mention Paul’s name, but in the past he has said he thinks possible candidates like Paul, as well as Sen. Marco Rubio, R-Fla., and Sen. Ted Cruz, R-Texas -- all in their first terms -- do not have enough experience to be president.

He said it was the president’s “profound lack of experience that has created the problems for us here in America,” stressing his own “eight years of service on the armed services committee” while he was in the Senate.

"Commander-in-chief is not an entry-level position,” he said. “[The] Oval Office is no place for on-the-job training, not in times like this.”

The pro-Clinton group "Correct the Record," responded to Paul's speech with spokeswoman Adrienne Elrod saying in a statement, "Rand Paul's brand of extreme isolationism would foster global instability."

She said "Americans want a tested and proven leader like Hillary Clinton."

ABC News’ Julianne Ferreira and Joey Morales contributed to this report.