Cain also said that he was relying on his book to improve his recognition among voters.

“Signing books helps to raise my name I.D.,” Cain said. “As a matter of fact, it’s not inconsistent to be on a book tour signing books as well as campaigning. Because we have integrated campaign events along with events related to this.”

At the time, Cain said he would consider picking up more book tour stops. But after Tuesday's debate in New Hampshire - in which the former Godfather's Pizza CEO and his 9-9-9 economic plan was the star - Cain said he planned to end the promotional tour.

"The book tour is over," Cain said. "We have run this very lean by design. We are now going to ramp up. We now have the money to do so. I didn't want to get out in front and commit to spending a whole lot of money before I knew that the American people were going to say, 'You know what? This long shot may not be such a long shot.'"

Cain's book is a mixture of policy, autobiography, and political prognostication that chronicles the candidate's life through a childhood in the South during the Civil Rights movement up through and including his current presidential run.