Philip Pullman's His Dark Materials trilogy has benefited from its inclusion in the BBC's Big Read by becoming the best-selling book in the survey, according to research.
Pullman won the Whitbread Prize in 2002
The success of the trilogy - which is treated in the suvey as one book - has seen it edge ahead of all the Harry Potter books, including the most popular in the series The Prisoner of Azkaban.
The His Dark Materials trilogy has now sold 25% more copies again than The Prisoner of Azkaban.
The BBC top 100 survey, which saw viewers voting for their favourite all-time book, was only published in alphabetical order but sales tracked by The Bookseller magazine indicate which books are proving popular to buyers.
The poll has had a positive effect on the publishing industry, with sales of the 100 listed books showing massive increases in some cases since its publication in May.
The Bookseller also took the list and compared the titles with sales data from 2002, revealing Lord of the Rings to be the biggest seller with nearly 900,000 copies sold.
In second place for 2002 was Pullman's trilogy which sold 748,099, followed by the four Harry Potter books in third, fourth, fifth and sixth position.
But sales following the publication of the Big Read made His Dark Materials by the Oxford author the most popular, with sales of 6,948 up to 24 May.
Harry Potter and the Prisoner of Azkaban was in second place followed by the Goblet of Fire, the fourth in the Potter series.
Brazilian author Paulo Coelho's The Alchemist was the fourth biggest seller following the Big Read list and was also the 10th most popular in 2002.
The Princess Diaries were made into a film starring Julie Andrews
Modern children's series The Princess Diaries by Meg Cabot was revealed as the fifth biggest seller in recent weeks, and in seventh place during last year, boosted by a movie starring Julie Andrews.
But interest in the Lord of the Rings trilogy has waned slightly since its resurgence in the wake of the movie adaptations.
Its sales following the Big Read survey put it at 20th in the list, compared to coming out top in 2002.
Sales data also shows readers are revisiting modern classics including Catcher in the Rye, To Kill a Mockingbird and Catch 22.
Later in the year, the BBC will whittle down the 100 books to a top 20 which will be championed by celebrity fans and the public will vote to decide the nation's favourite.