Twenty eminent election forecasters explain their forecasting models and offer their predictions for the 2012 US presidential election, in PS: Political Science and Politics, published by Cambridge University Press for the American Political Science Association.

With a range of forecasting models and experts, the forecasts vary, but none are predicting a big win either way; yet another indication that 2012 is shaping up to be another very close race.

Five models predict a modest to close plurality for (though three of these are on the cusp of predicting a toss up), five predict a modest to close victory for , and three regard the election as a toss up. The forecasts range from predicting a 53.8% vote for Obama to a 53.1% vote for Romney.

Editor of the journal's forecasting symposium, James Campbell, said: "It is difficult to say exactly why the forecasts vary as much as they do this year, but it appears that those that rely more on the existing holder of office and early public opinion indicators tilted more toward Obama, while those that depend more on objective tipped toward Romney."

The thirteen forecasts and introduction will be published in the October issue of PS: Political Science and Politics, scheduled for release in late September. Articles will be available online, for free, for a limited time at http:// journals.cambridge.org/psc.