Cain's popularity has steadily risen over the past weeks, and a recent CBS poll places him tied with Mitt Romney at the top of the field of Republican candidates.
The candidate dubbed "the Herminator" signed copies of his memoir "This is Herman Cain!" at the Pentagon City Costco on S. Fern Street from noon until 1 p.m. He discussed his campaign, Sarah Palin's supporters and the Occupy Wall Street protests.
Following the book signing, Cain, former CEO of Godfather Pizza, headed to the Omni Shoreham Hotel in northwest D.C.