It's 266 pages long and has nothing but a table of contents, chapter names and bibliography. But it carries a message.

A joke book "written'' by a conservative author and filled with blank pages in a dig at Democrats is the top selling book on Amazon.

Reasons to Vote for Democrats: A Comprehensive Guide consists of 266 pages. It has a table of contents, chapters and a bibliography, but no words on the pages other than the book and chapter titles. It's billed in the description as "a political treatise sure to stand the test of time".

As of Friday morning, it was Amazon's best-selling book. The paperback is available for about US$8 [NZ$11.50].

Author Michael J. Knowles tells Fox News that when he took a look at the Democrats' "record and reasons to vote for them", he thought "it was probably best to just leave all the pages blank".