Most will end up in piles of remaindered copies or lie unread in the rooms of students. As literature, they have few redeeming qualities, while their relationship to reality is often questioned, as is their true authorship.

But the presidential candidate's book has become as much part of the race for the White House as the wooing of wealthy donors in Manhattan, trudging through the snows of New Hampshire and endless stump speeches in Iowa.

With the 2008 election arguably the most open contest since 1928 – the last time no sitting president or vice-president ran for their party's nomination – a record number of turgid tomes are on offer.

Today sees the re-release of Hillary Clinton's It Takes a Village, 10 years after it was published when she was First Lady. Among its insights is that "our village has changed over the last decade" in ways ranging from "the impact of the internet to new research in early child development".

Al Gore is due to publish The Assault on Reason, billed as an examination of how "the public arena has grown more hostile to reason", while Senator John McCain is working on Hard Call, his fifth book, which will explore historic decisions in politics, history and science.