Oprah doubled sales of the late Sen. Edward Kennedy's memoir "True Compass" when she featured Kennedy's widow Vicki.

The hardback book sold 100 percent more copies the week after Vicki's appearance on the top-rated chat show.

The surge in sales means the paperback version is now being delayed until 2011 although the e-book will come out on Christmas Day.

Vicki's interview with Oprah was her most extensive since Kennedy died of brain cancer on Aug. 25.

A spokesman for the publisher Twelve said "True Compass" sold 11,000 copies the week before the show, more than 22,000 the following week and more than 32,000 the next week, bringing the total to more than 400,000.

Kennedy reportedly received an advance of $8 million for "True Compass," which had an initial print run of 1.5 million copies.