Former President Clinton's (search) memoirs have sold nearly 1 million copies in less than a week, his publisher said Monday.

Publisher Alfred A. Knopf said 935,000 copies of "My Life" (search) had been sold by the end of Sunday, and the million mark should be reached soon.

"It's a certainty, we just don't know what day it will be," said Knopf executive director of publicity Paul Bogaards. "It could be today, it could be tomorrow."

The book went on sale last Tuesday, and sold more than 400,000 copies in the United States in the first day, the biggest debut ever for a nonfiction book, and double the believed previous record holder, Sen. Hillary Rodham Clinton (news - web sites)'s "Living History."

Figures for international sales were not yet available.

The book is already in its third printing, with an expanded print run of about 2.6 million copies.