Herman Cain defends conducting book tour during presidential campaign

"We had six days carved out where we combined signing books for the release of the book, and a mixture of campaign events. I didn't do a month-long book tour! We did six days where half of the events were signing books, and the other half of the events were campaign events."

-- Herman Cain, the Republican presidential candidate, on critics who say his candidacy is just a promotional stunt for his book, "This Is Herman Cain! My Journey to the White House," and that he's not taking the campaign--and his unlikely rise in the polls--seriously. Cain told CNN's Anderson Cooper after last night's pushy debate in Las Vegas that his campaign is raising money and adding more staff in New Hampshire, Iowa, South Carolina, Florida and several other states.

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