The Obama campaign was provided with reports from the Secret Service showing a sharp and disturbing increase in threats to Obama in September and early October, at the same time that many crowds at Palin rallies became more frenzied. Michelle Obama was shaken by the vituperative crowds and the hot rhetoric from the GOP candidates. “Why would they try to make people hate us?” Michelle asked a top campaign aide.

The Republican vice presidential candidate attracted criticism for accusing Mr Obama of “palling around with terrorists”, citing his association with the sixties radical William Ayers.

The attacks provoked a near lynch mob atmosphere at her rallies, with supporters yelling “terrorist” and “kill him” until the McCain campaign ordered her to tone down the rhetoric.

But it has now emerged that her demagogic tone may have unintentionally encouraged white supremacists to go even further.

The Secret Service warned the Obama family in mid October that they had seen a dramatic increase in the number of threats against the Democratic candidate, coinciding with Mrs Palin’s attacks.

Read more on this from Newsweek and Telegraph.

Newsweek has released highlights of its Special Election Project, which allowed reporters to gather behind-the-scenes information on the presidential campaigns with an agreement that none of their reporting would be published until after Election Day.

You can read a summary of their report here, and the first chapter of their book here.

For the complete contents of the project, come back to Newsweek.com in the coming days.