2019 European Parliament Election Predictors

Alex McHaddad, May 27, 2019

Top Parties in each EU State. Blue: European People's Party (center-right). Light Blue: European Conservatives and Reformists (conservatives). Yellow: Alliance of Liberals and Democrats for Europe (moderate). Red: Party of European Socialists (center-left). Orange: Europe of Freedom and Direct Democracy (anti-EU; varied ideology). Pink: Europe of Nations and Freedoms (anti-EU and far-right).

Europe has a parliament?

Since 1979, voters in Europe have cast ballots in quintennial elections for a continental assembly, the European Parliament. This body acts as the lower house of the EU's legislature, opposite the Council of the European Union, composed of member state cabinet members (not to be confused with the European Council, the ultimate governing body of the EU).

As in most Western democracies, parties compete for seats in the European Parliament. The three main parties are the conservative European People's Party, the progressive Party of European Socialist, and the moderate Alliance of Liberals and Democrats for Europe. All three parties won seats in the Parliament this session, competing with 5 other main competitors.

Predicting election outcomes in EP elections is much more complicated than the United States for a variety of reasons. All but 3 EU states elect their MEP's (Members of European Parliament) from a single nation-wide constituency, rather than by Districts as in the United States, with seats apportioned to parties based on share of votes. Belgium, Ireland, and the United Kingdom each elect MEP's by District, but voters in each District ultimately vote for several candidates whose seats are also apportioned based on vote share.

Most Popular European Party affiliate in each country. Blue: EPP. Light Blue: ECR. Yellow: ALDE. Red: PES. Orange: EFDD. Green: Greens/European Free Alliance (Greens and separatist movements). Purple: European United Left/Nordic Green Left (communists/socialists).

Adding to the difficulty of predicting outcomes is the fragmentation of member parties. Elections in the United States of America are dominated by the Democratic and Republican Parties, both of which have one statewide affiliate. For a variety of reasons, each European-wide Party may have several affiliates in a given country, who may partner or compete for the same seats; some affiliates will reach across the aisle and compete with affiliates of different parties for seats. Facebook likes proved to be a statistically significant predictor of electoral success only in Malta, where just 2 parties won EP seats.

Primaries are not held for MEP candidates; instead, candidates are chosen by party members at conventions. Predicting outcomes based on the membership in each party would be valuable; however, parties are not required to publish their membership figures. As a result, elections results in no EU member state could be predicted by party membership. Bulgaria, Croatia, Poland, and Slovenia party membership figures were technically predictors of a party's vote share, but these correlations were calculated with minimal data. Membership figures from Bulgaria, with 5 out of 7 mainstream parties reporting participation, show a 92% correlation with vote share.

Total vote share in the European Parliament's 2019 election elections, however, was predictable at the continental level. Lead candidates for each party who would be offered as the nominee for President of the European Commission (similar process and position as Prime Minister) were not statistically significant. However, vote share in the European Parliament was predicted by each party's performance on social media.


Each European-wide party's Facebook page like tally had a statistically significant correlation to its share of votes cast in the election (91.342%) as well as the number of seats it obtained in the European Parliament (91.343%). This calculation occurred despite ALDE's outsize performance on social media over PES, which actually received the second largest number of MEP's.


Twitter showed statistically significant correlations of 90% between a party's number of followers and its vote share as well as number of MEP's.* The top three parties in the European Parliament came in the same place as they did when counting total Twitter followers.

EPP lead candidate Manfred Weber of Germany. A member of the Christian Social Union of Bavaria party, Weber formerly served as President of the European Parliament (analogous to Speaker of the US House of Representatives). Photo credit: Manfred Weber's Facebook page.

Wait, Europe has a Prime Minister?

The European Union is a complex entity with the same governing institutions as a modern republic. Ultimate executive and military authority is vested in the European Council and its President, the details of the Council's will are drafted by the European Commission, and its proposals are approved by the European Parliament and Council of the EU prior to implementation by the European Commission. In many countries, executive and administrative authority is respectively split between a President or monarch, and a Prime Minister. The Prime Minister is usually a member of and leader for their party in the national parliament.

PES lead candidate Frans Timmermans of the Netherlands. A member of the Labor Party, Timmermans is First VP of the European Commission. Whereas the VP of the US is presiding officer of the Senate, the designation of VP is an additional responsibility for a member of the European Commission with other duties. Photo credit: Frans Timmermans' Facebook page.

Since 2014, the EU has observed a process wherein each party chooses a lead candidate who is nominated to be President of the European Commission by the European Council based on their party's share of seats. The European People's Party won a plurality of seats in the European Parliament in 2019, and the European Council nominated their lead candidate, Jean-Claude Juncker, to be Commission President. This process is expected to be observed again in 2019, a process that remains clear-cut since EPP won another plurality.

The EPP, PES, ECR, and EFA all nominated a single lead candidate, while the Greens and GUE/NGL nominated 2 lead candidates. ALDE nominated 8, without rank, though the senior figure is longtime EP caucus leader Guy Verhofstadt, who would most likely have received the nomination following a successful ALDE victory. Ultimately, ALDE came third to PES and EPP, for the fifth election in a row.

The combination of multiple candidates per party made calculating correlations with total continental vote share and seats impossible. A selection of candidates including the singular nominees of EPP, PES, ECR, along with Ska Keller of the Greens, Violeta Tomic of GUE/NGL, and Guy Verhofstadt of ALDE yielded correlations between 24-26%. Adding ENF co-leader Nicolas Bay and EFDD leader Nigel Farage (both of whom would be caucus leaders but ultimately aspire to abolish the EU and would not accept a nomination for President) makes the correlations negative. The current pool of lead candidates may not ultimately be as popular as the parties they lead, casting the long-term success of the lead candidate process in doubt.

ALDE lead candidate Guy Verhofstadt of Belgium. A member of the Open Flemish Liberals and Democrats party, Verhofstadt served as Prime Minister of Belgium before election to the European Parliament and eventual caucus leader for ALDE. Photo credit: Guy Verhofstadt's Facebook page.

A Fragmented Election

This election was difficult to predict via traditional polling methods. The first unexpected outcome occurred when the Labor Party in the Netherlands took first place, possibly because the country put forth a major party lead candidate. Green/EFA candidates took forth place overall, up 19 seats from the 2014 election. Far-right ENF candidates made far fewer gains than predicted, with lead candidate Marcell de Graff failing to win election in the Netherlands. Meanwhile, the total number of ECR MEP's dropped by 17.

Social media following appears to have successfully predicted outcomes in the European Parliament election, despite overcoming the staggering odds presented by the fragmented party system. It is likely that continuing fragmentation of the system will make this more difficult in 2024, when the next European Parliament elections are scheduled. Until then, make sure to like and follow your candidates on Facebook to increase their exposure!

*Note about Parties: The Green Party and European Free Alliance are legally separate parties, but they caucus together in the European Parliament. This caucus is grouped together in vote tallies during elections and maintains a Facebook page and Twitter profile; these profiles are used in these calculations.