Unlike Senator John McCain who presented himself as a maverick in the 2008 presidential campaign, Republican hopeful Herman Cain is a true political outsider.

The surprise leader in opinion polls of Republicans seeking to take on President Barack Obama in 2012, the one-time fast food executive Cain is running for the world's most important job despite never having held elected office.

By contrast, McCain was a Washington heavyweight who had served in Congress for a quarter of a century when he launched his second presidential campaign and lost to Obama.

With voters tired of Congress' failure to revive the economy, Cain is flaunting the mantle of newcomer.

I don't talk politician, he said at a rally in Tennessee over the weekend. I have grown up telling it like it is and I am going to continue to tell it like it is, he said.

But Cain's lack of political experience may hinder him, as his 9-9-9 tax plan comes under attack and rivals try to show him as inexperienced with policy and dealing with the media.

A black from the Deep South, Cain raised eyebrows in September when he said that most African Americans were brainwashed into rejecting conservatives.

Cain, 65, has gone against the grain since his youth, a trait that has helped him beat advanced colon cancer and shake up struggling fast food businesses.

Cain is the son of a maid and a janitor who went on to become the driver for Coca-Cola's CEO in Atlanta, and his family was hardworking.

He was brought up on Albert Street, a set of modest houses in a mainly black neighborhood built in the 1960s for upwardly mobile families.

They were strivers, community historian and librarian Janice Sikes Rogers said of the type of African Americans who lived on Albert Street. They were ambitious. They were people who wanted something, people who wanted more, she said.

Cain was educated in the 1960s at Atlanta's prestigious Morehouse College, a center of civil rights protest, yet he avoided involvement in the movement.

He did not get a feel for what the struggle was all about, said Amos Brown, a Baptist pastor who remembered Cain from Morehouse. He heard about it. He saw something of it and he was not in it, Brown said. The college's most famous graduate was Martin Luther King.

Cain made his name in business by shaking up Burger King's restaurant operations in the Philadelphia area in his 30s and then converted the loss-making Godfather's Pizza into a generator of profits before buying the company out.

He cut costs at Godfather's and says he restored the quality of the product, assembled a strong management team and invigorated demoralized staff with a clear mission.

COMPLEX MAN, SIMPLE MESSAGE

That knack for delivering a straightforward message is at the core of Cain's presidential bid.

My campaign is catching fire because my message is specific. I'm offering specific solutions to specific problems that this nation faces and they are understandable and the American people are connecting, he told Reuters.

Cain's 9-9-9 plan foresees streamlining the tax code into 9 percent income, corporate and national sales rates.

It has a catchy ring to it although tax experts have cast doubt on the amount of revenue it can raise and some Republicans fear it would open the door to higher sales taxes. Cain admitted on Sunday that 9-9-9 would raise taxes on some Americans.

Cain and his economic adviser Richard Lowrie devised 9-9-9 over several weeks this year.

In a private meeting, I asked Mr. Cain: 'How bold do you want to be?' And if you're familiar with how big and deep his voice is, he just leaned in and said 'BOLD!' And I thought, well, I can work with that, Lowrie said.

Despite his campaign role as outsider, Cain was a mainstream economic policymaker in the mid-1990s as chairman of the Kansas City arm of the Federal Reserve, a body deeply mistrusted by Tea Party fiscal conservatives.

And two of his campaign staffers worked for Americans for Prosperity, a group backed by the billionaire Republican insiders Charles and David Koch.

Cain's campaign has only 35 people on the payroll but he is hiring fast as some polls show him at the head of the Republican race.

Cain placed first in an NBC-Wall Street Journal poll among Republican candidates and second in a Reuters Ipsos poll, behind former Massachusetts Governor Mitt Romney last week.

But few members of his staff have significant national campaign experience and one person familiar with his bid called it a fly by the seat of your pants operation with thin staffing in early voting states.

He has been hit my staff resignations. Over time, I just realized he didn't have a good grasp of all the issues, said one former staffer.

Even though he is trying to court Tea Party backing, Cain differs in tone from the often boisterous movement that has spearheaded Republican anger at big government. In 2008, Cain took over as a talk show host on WSB Radio in metro Atlanta, so programmers had to move syndicated conservative host Michael Savage to a later slot.

The difference between the two men's style was marked.

Both are conservatives but in contrast to Savage, who often sounded angry and would shout at callers who disagreed with him, Cain was unflaggingly polite.

He is affable and homespun to the point of being quirky.

In his autobiography, This Is Herman Cain! My Journey To The White House, he coins the term CEO of Self to describe his own version of self improvement.

He muses about sitting behind the desk in the Oval Office on his first day in the White House and preparing with his wife Gloria for what he has already decided will be the sole inaugural ball.

Bear with me for just a minute more as I confirm who I am, he says in the book's concluding words. It's obvious: I'm the president of the United States of America.