Dr. Benjamin Carson, director of Pediatric Neurosurgery at Johns Hopkins School of Medicine, speaks to the Conservative Political Action Conference at National Harbor on March 16. (Jonathan Ernst/Reuters)

The voice mail greeting at Benjamin Carson’s Johns Hopkins Hospital office, where he is the director of pediatric neurosurgery, stretches for almost eight minutes.

There are instructions for patients calling with medical emergencies. There’s information for fans who want to get one of his books autographed or book Carson as a motivational speaker. The most recent addition followed his National Prayer Breakfast appearance last month: “There has been an overwhelming response to Doctor Carson’s speech,” it warns. “If you are calling with remarks . . . please do not leave a message on this voice mail since it will impact our ability to get messages from patients.”

Carson’s voice mail greeting, which has been growing in 20-second increments for almost two decades, reflects the many identities that he has added through the years. The list includes world renowned neurosurgeon, author, speaker, inner-city folk hero, role model to evangelical Christians and, most recently, rising conservative political star.

His latest brush with fame followed the prayer breakfast speech in which he criticized the president’s health-care overhaul, called for a flat tax and warned that the enforcers of political correctness had put a dangerous “muzzle” on debate in the country. To the delight of conservatives, Carson delivered the address with a stone-faced President Obama sitting a few yards away.

Within days of his remarks, Carson was being touted as a possible presidential candidate by the Wall Street Journal. He got one of the most enthusiastic receptions at the recently held Conservative Political Action Conference, where he stoked speculation that he may, just may, be willing to run for president.

After a several-day onslaught from fans and the media, many wanting to know his potential political plans, Carson has eased away from suggestions he may have his eyes on the White House. The 61-year-old doctor now says the likelihood of a presidential run is “incredibly small.” What he really wants is a second career in television when he retires from Johns Hopkins later this year.

“Maybe if you write about it in your article, somebody will say, ‘Let’s do it,’ ” he said in an interview.

For now, his small office staff is struggling to manage the crush of attention from smitten conservatives and find time for his brain surgery patients between his sit-downs with the national media.

“Here you go Mister Hollywood,” joked Carol James, Carson’s physician assistant for the last 31 years.

She dropped off the latest unsolicited offering. It was a box of buttons bearing the letters “P.C.,” crossed out with a red slash, and a note from a supporter in Gulf Breeze, Fla.

“When you spoke on national television,” the fan wrote, “I knew I must send you these buttons.”

‘Treading new ground’

Carson relays his personal story these days with the practiced confidence of someone who has been telling and retelling it for decades. Each of his anecdotes has been honed to make a specific point aboutthe importance of religious faith, self-reliance and education.

“I was a horrible student. Most of my classmates thought I was the stupidest person in the world,” he says regularly of his early elementary school years. “They called me dummy.”

In the fifth grade, Carson’s illiterate mother pressed him to read at least two books a week and submit book reports that she pretended to grade. Within a year, he was among the top students in his class and a series of remarkable accomplishments followed. Carson vaulted from his inner-city Detroit high school to Yale, earned a medical degree at the University of Michigan and became the nation’s youngest chief of pediatric neurosurgery at Johns Hopkins Hospital.

“When I decided to become a neurosurgeon, there had only been eight black neurosurgeons in the history of the world,” he said. “Really from the very get-go, I was sort of treading new ground.”

At Hopkins, Carson pioneered a lifesaving surgical procedure for children with epilepsy and in 1987 vaulted to national recognition when he led a surgical team that successfully separated twins conjoined at the head.

A few months later he signed a contract with a small Seventh-day Adventist press to publish his autobiography. Before the book was finished, Carson and his co-writer had concluded that his life story was worthy of much wider distribution and changed publishers.

“Some people who were very well versed in literature said: ‘This book is amazing. This is going to be a classic,’ ” Carson recalled. “I was a little skeptical, but they were right.”

The book, titled “Gifted Hands,” was published in 1990 by Zondervan, the country’s largest Christian press, and was an immediate hit with inner-city teachers who saw the black physician as a role model for their students.

Demand for Carson as a speaker soared. “I lost four secretaries in one year because people were calling and putting so much pressure on them,” Carson recalled.

Carson and his wife started a nationwide scholarship program to reward academic achievement — and he was name-checked on the HBO television drama “The Wire.”

Some of Carson’s fellow doctors have criticized his relatively low output of scholarly articles in medical journals. But in the Christian publishing world, Carson has been prolific, writing four books since 2000. “Gifted Hands” has sold almost 2 million copies and has become a standard part of many evangelical home-school curricula.

“It just sells and sells and sells,” says Stan Gundry, a senior vice president at Zondervan, a Christian media company and unit of Harper Collins.

As a public speaker, Carson has been drawing big audiences since the mid-1990s. Six times a year, as many as 800 students pack into the main auditorium at Johns Hopkins Hospital for one of his “Think Big” lectures in which he shares his faith-based philosophy. Last summer, a medical school in Lagos, Nigeria, was named after him.

“For him, the attention was natural,” said James, his longtime physician assistant. “For the rest of us, it was crazy. . . . This has become much, much more than a medical practice. With each new book, movie or prayer breakfast speech there is a whole new surge of people who are interested in him.”

Dire warnings

Carson’s embrace of a more overtly political identity began last year with his latest book, “America the Beautiful,” the first that he published without a professional co-writer. He wrote it with his wife.

In contrast to his earlier, sunnier works, the book argues that the United States is in the midst of a crisis that could lead to its destruction. “I was extremely concerned about what kind of country we were leaving for our children,” he said. “I thought maybe I could wait until I retired. But I decided I couldn’t.”

Carson delivers his dire warnings in a calm, soothing voice, but speaks with the certainty and, at times, extreme self-confidence of an accomplished neurosurgeon.

“I think everyone needs to hear what I am talking about,” he said in an interview.

His economic philosophy reflects the tea party movement and its deep concern about the country’s growing national debt.

He draws his ideas on simplifying the tax code from Christianity. “When I pick up my Bible, you know what I see? I see the fairest individual in the universe, God, and he’s given us a system,” Carson said at the prayer breakfast. “It’s called tithe.”

At the Conservative Political Action Conference a few weeks later, Carson suggested that government should rely on churches to provide a safety net for the poor and get out of the social welfare business. “Why is the government trying to duplicate what [churches] are supposed to be doing?” he asked.

Hospital as ‘haven’

Carson has long viewed his medical practice as a place where he can escape the demands of the more public aspects of his life. “When I go into the hospital or the operating room, it is like a haven,” he said. “A safe haven. You forget about all that other stuff and just concentrate on the patient.”

Today, his cramped office looks as though it has been frozen in time. A sickly cactus sits on his small office’s lone window sill. Pushed up against the wall is a frayed, red couch that could have been salvaged from Goodwill. Carson has taken naps on it between late-night surgeries for more than 20 years.

The stress and demands of his newfound fame have in recent weeks invaded his medical practice. Carson’s office manager of 17 years describes the month of February as a “total blur.”

His physicians assistant, who has been with him for 31 years, complains that he barely has time to operate on his patients. “We are trying to squeeze them in between every media organization in the world,” she said

The sudden outpouring of attention, meanwhile, has left Carson pondering his next act. He is set to retire from his medical practice in about 100 days.

“It wouldn’t surprise me if I decided to do more things on television,” he said. Carson was dressed in surgical scrubs and scuffed tennis shoes. His cellphone beeped.

“I got to go,” he said. “They are ready for me in the operating room.”

Before he left, Carson finished his thought. He would like to do a show that focuses on “educating the American populace about things that are essential to our freedom,” he said in his soft, steady voice. Or he would like to try a show that would bring together people who hold opposing views on critical issues that are dividing the nation. Carson would then help them seek a middle ground or resolution.

“If the proper venue was presented, I would probably accept such a thing,” he said.