Bill Simon Pacific Palisades, Calif.; Maui, Hawaii; Sun Valley, Idaho

Co-chairman of William E. Simon and Sons LLC, an investment firm he co-founded in 1988 along with his father, William Simon, a former U.S. Treasury secretary; co-chairman of the Cynthia L. and William E. Simon Jr. Foundation.

Wealth:

Undisclosed

Power/Influence:

Simon was the most influential member of Giuliani’s presidential campaign following his appointment as national policy director in February 2007. He was referred to as Giuliani’s “professor,” and McCain has called him a “conservative leader.” Prior to that, Simon ran for California governor. Once the base of the national GOP, California has increasingly become a Blue State. But it remains important for the Party, and Simon is Reagan’s heir there.

Role in Campaign ’08:

Simon endorsed McCain in January, saying his fellow Republican’s “experience and judgment are precisely the qualities needed in our next commander in chief.”

Who Knew: Simon dropped out of the running in the 2003 special election for California governor, but still finished 12th in a field of 135 candidates.

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