With polls showing Obama’s post-convention lead has largely evaporated, Facebook targeting by the Democrats and Republicans could help decide this year’s US presidential election. This is according to a study undertaken by the University of California, San Diego, which shows that a message on Facebook can boost voter turnout by 2.2%.

More than sixty million US Facebook users saw a pro-voting message at the top of their Facebook page back on 2 November 2010, the day of the Congressional elections. It included an ‘I voted’ button, and the profile pictures of friends who had already clicked it.

Just being exposed to the message persuaded an extra 0.4% of people to vote. However, another 1.8% decided to vote, based on the fact a close friend had also seen the message. This 2.2% uplift could have changed the 2000 presidential election.

If good Facebook targeting can swing an election, what can it do for your brand?