(Bloomberg News) Herman Cain is multitasking, and he may be about to lose his cool.

"You see, this is the part that I really have to show my patience," Cain says as he autographs a well-wisher's baseball, gets heckled by a disgruntled Republican voter and crosses a busy street in Concord, New Hampshire -- all while trying to explain to a gaggle of reporters how he can win a third of the black vote in the United States.

His wife reminded him: "'Herman, remain cool'" during last week's debate with his Republican rivals in Hanover, Cain said. He did that and more, grabbing the spotlight with his 9-9- 9 tax initiative and hitting back when competitors belittled the plan -- and him -- during the session.

Now Cain, 65, a former Godfather's Pizza chief executive and radio host surging in Republican primary polls, is scrambling to transform his fledgling presidential bid -- heavy on branding, personality and catch-phrases but light on organization, discipline and policy details -- into a well- oiled, well-funded competitive campaign machine.

'Lean and Mean'

That means rapidly expanding a politically inexperienced staff of 35 -- Cain calls his operation "lean and mean" -- into a much larger and more seasoned organization in important primary states, boosting fundraising and filling in the considerable blanks in his policy plans.

Above all, it means preventing himself from becoming the latest in a succession of fiscally and socially conservative candidates -- including Texas Governor Rick Perry and Minnesota Congresswoman Michele Bachmann -- who have briefly challenged former Massachusetts Governor Mitt Romney for the title of Republican frontrunner, only to lose momentum.

"I won't fizzle," Cain promises a voter at a Concord restaurant who asks if he's in the race "for the long haul."

Yet Cain knows he has a narrow and shrinking window of time to ensure his staying power, with key states jockeying to hold primaries as early as possible and New Hampshire now threatening to set its contest for early to mid-December.

And he has little to say, apart from an ice cream analogy that's become a favorite in recent days, about how he can do so.

"Will I be the flavor of the week?" Cain quipped last week. "Well, the answer is an emphatic 'No,' because Haagen Dazs black walnut tastes good all the time."

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