(Bloomberg Politics) — Dr. Benjamin Carson, the retired neurosurgeon who has been lighting up conservative crowds across the country, called for the country to move in a “new direction” Thursday while pressing Republican lawmakers to propose a viable alternative to the Patient Protection and Affordable Care Act (PPACA) before trying to repeal President Barack Obama’s cornerstone domestic policy achievement.

“They need to grasp a health care alternative before they try and remove Obamacare if they really want to gain some traction,” Carson told the crowd at the annual Conservative Political Action Conference (CPAC) in National Harbor, Md. Carson has proposed a system of health savings accounts to cover most individual health care needs.

Carson, who has been hiring senior staff for a potential presidential run, ticked through a series of critiques of the current administration on domestic and foreign policy. He said radical Islam “threatens to destroy” the U.S., though he pointed to “the Shia in Iran” as “every bit as dangerous if not more dangerous” than the Islamic State.

The first speaking slot of the event is never ideal, with the traditionally boisterous crowd trickling in over the course of the remarks, and the ballroom was only half-full for his appearance. Still, Carson, who is polling higher than top potential establishment candidates Jeb Bush, the former Florida governor, and New Jersey Gov. Chris Christie, in surveys of potential Iowa Republican caucus goers, received a standing ovation on his introduction.

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Raised in poverty in Detroit and Boston, Carson rose to become one of the world’s premier neurosurgeons, the first to successfully separate twins conjoined at the back of the head. He was awarded the Presidential Medal of Freedom by President George W. Bush, has more than 60 honorary doctorate degrees, and serves on the boards of Kellogg Co. and Costco Wholesale Corp. His foundation, Carson Scholars Fund, is operating in all 50 states and has pledged nearly $6 million in scholarships to students for academic and humanitarian achievement.

That background, along with his blunt breakdowns of the perceived failings of the country under Obama, has helped make him a regular in the top tiers of polls throughout early Republican primary states.

His remarks Thursday tracked closely with a stump speech that has been refinedin events in as many as four or five states per week over the past year. Carson attacked Democrats for social welfare programs and chided Republicans who declined to speak out about their beliefs.

“We have to stop sitting silently by and express ourselves,” Carson said.

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