One of the features that will surely differentiate the 2012 US presidential elections from the 2010 midterm elections will be higher turnout: people the world over are more likely to turn out in more important elections, and there is a long pattern of precisely this behavior in US presidential and midterm elections.
Received wisdom regarding European politics is that higher turnout benefits the party of left, or, in the case of the US, the Democratic Party. After all, supporters of left parties tend to have lower socio-economic status, and as we know that socio-economic status is an important predictor of turnout, it stands that as a higher proportion of the population of the population votes this “turnout bias” for right-wing parties should decrease, and therefore the left should benefit.
Recent research by Henning Finseraas of the Norwegian Institute for Social Research and Kåre Vernby of Uppsala University presented last week at the inaugural European Political Science Association Annual Conference, however, casts doubt on this simple story. They use a Norwegian reform of early voting rules to get a clean way to study the effect of an increase in turnout on election results. They find that while the traditional story is true – increased turnout helps the social-democrats in Norway – it is also the case increased turnout helps the radical right party in Norway. Both the tradional right wing party and and the “left-libertarian” party in Norway were hurt by the increase in turnout. Their explanation for these findings is that radical right parties in Europe also tend to draw support from those with lower social economic status, and thus the mechanisms that normally help higher turnout have a positive impact on the vote for left parties should apply here as well. Their take home point is that we need to stop thinking about the effect of turnout on election results in simple dichotomous matter of whether this helps the left or the right. The full paper is available here.
What does any of this have to say about the United States in 2012? With the appropriate caveats about what a study of voting in Norway can teach us about voting in the US, my own personal working assumption has been that Obama and the Democratic Party would get an automatic boost vis a vis 2010 due to a more left leaning composition of the electorate for the presidential election due to higher turnout. The wild card here is the Tea Party, which one could conceivably think of in terms similar to a radical right party in the European sense, at least in so far as it has positioned itself to the right of the traditional right wing party in the country. While the Tea Party will not run a separate candidate for president, its supporters can be expected to provide support to whomever the eventual Republican nominee is. However, the mechanism proposed by Finseraas and Vernby—lower socio economic status of far right supporters—does not look likely to be at play here, e.g., see this NY Times Poll claiming that Tea Party supporters are “wealthier and more well-educated than the general public”. So we are potentially in the interesting situation whereby if the authors got the story but not the mechanism correct, then we may expect to see the turnout increase in 2012 relative to 2010 not help the Democrats as much as we would expect if turnout also goes up among Tea Party supporters; however, if the authors got the mechanism (socio-economic status) correct, then the US’s “radical-right” party should not be expected to benefit from an increase in turnout as much as Norway’s did.