Forecasting the Italian Election: The Impact of Small Parties

In our latest update, we have shown how our predictions are affected by the introduction of a "fatigue effect".  This effect would penalize the Democratic Party for having led the executive in the last five years. Specifically, in the context of our forecast, voters are expected to subtract about three percentage points to the Democratic Party compared to what socioeconomic fundamentals would suggest. Not a trivial loss for Matteo Renzi's camp, especially when translated into seats: 35 candidates would lose their place in Montecitorio to the advantage of their competitors. However, we have so far neglected the potential impact of small parties' performances on March 4th. In fact, we have gathered all these minor formations under a generic "Others" label, which is expected to gain as many as 76 seats in the upcoming race. It is now time to open this black box, and see how such seats are bound to alter the balance of strength in Italy's future Chamber of Deputies.

As previously specified, however, our forecast can only predict the vote shares of the 5 parties that have already run in the last legislative election, dating back to February 2013. Therefore, we have used the latest YouTrend's super-mean of polls to get an idea of how the remaining votes are likely to be shared across the different minor parties that form our "Others" group. Among them, the most competitive one is certainly Free and Equal, the splinter faction of the Democratic Party led by the former Speaker of the Senate, Pietro Grasso.  As of now, this is the only formation that is expected to overcome the threshold of 3% of vote shares that is necessary to take part to the allocation of seats assigned in multi-member districts.

Our prediction of vote shares and seats from February 21st, gathering all minor parties together under the "Others" label.

How seats change when the votes of allies are redistributed to the Center-Right coalition and to the Democratic Party.

All the other parties, some of which are additional allies of the Democratic Party (+Europa, Insieme, Civica Popolare) or the Center-Right (Noi con l'Italia), will probably see their votes and seats redistributed to their stronger allies. This will have a major impact on the overall size of Parliamentary delegations, shrinking the one of the Five-Star Movement to the benefit of the Center Right and, most important, the Democratic Party. A quick comparison of the tables above, in fact, gives a sense of how the Democratic Party would fully recover from the negative incumbency shock, and get as many as 162 seats.

A substantial part of this bonus would come from single-member districts, where the Democratic Party is set to regain18 seats thanks to the contribution of its allies. Interestingly, almost all such seats would be snatched from the Five-Star Movement in some highly contested constituencies of Central and Northern Italy, where Matteo Renzi's party used to have its strongholds. As for the Center-Right, an overall gain of 30 seats would project it closer to the absolute majority in our forecast, even though 37 seats still look like a difficult gap to close.

Finally, one important caveat: Italy's current electoral system makes it extremely hard to figure out who will actually be getting the seats in Montecitorio. In particular, a major source of uncertainty is the result of Emma Bonino's party, +Europa. Probably the strongest ally of the Democratic Party, it has been performing better and better in polls as the weeks passed, and it has a fairly high chance of actually overcoming the 3% threshold and gain some seats from multi-member districts. If this will turn out to be the case, 10 to 15 seats that are currently assigned to the Democratic Party in our prediction table would instead accrue to this formation, thus redrawing the balance of power both within the center-left coalition and in the Parliament as a whole.

About the authors

Massimo Pulejo is a Pre-Doctoral Fellow at Bocconi University, Department of Policy Analysis and Public Management.

Piero Stanig is Assistant Professor of Political Science at Bocconi University, Department of Policy Analysis and Public Management, and a fellow of the Carlo F. Dondena Research Center. 

Thanks to Giovanni Da Fre' for excellent research assistance.