This was the election that was never meant to happen. Britain should have left the EU and its parliament behind on the 29 March 2019.  Yet, to comply with the EU’s requirement for a six-month extension of Brexit, the UK is now gearing up to hold European Parliament elections on the 23 May to elect a new set of MEPs.

These new British MEPs may have a very short tenure in the parliament, as the clock is ticking down to Britain’s new exit date on 31 October 2019. Ironically, however, these may be Britain’s most important European elections yet.

But why do these elections matter if Britain is on its way out anyway? They matter because of their potential to shape the Brexit process, UK politics, as well as the composition of the European Parliament.

First and foremost, these elections will be about Brexit. They will offer a deeply divided electorate a chance to express its views on Brexit as well as its dismay with the government’s handling of the negotiations.  As European elections are regarded as less important than national ones, voters use them as an opportunity to punish poorly performing national governments and vote for smaller and more extreme parties. In the UK, the success of smaller parties is further buoyed by the use of proportional representation in EU elections, in contrast to the first-past-the-post system used in Westminster elections. Indeed, Nigel Farage’s United Kingdom Independence Party (UKIP) topped the polls in the 2014 EU election, while gaining just a single seat in the following 2015 elections to the House of Commons.  In the 2019 British EU elections, the fragmentation will be further exacerbated by the salience of voters’ Brexit identities and the arrival of new parties campaigning just on that issue: Farage’s new Brexit Party and the pro-Remain Change UK.

Polling suggests that vote choices will be mainly a reflection of how voters feel about the Brexit issue. Most Leavers are likely to vote for the Brexit Party, with the much-weakened governing Conservative Party as a second choice. On the Remain-side, the vote is scattered across four different parties: Labour looks likely to command most support among Remain voters – despite the party’s ambiguous stance on whether it is pro-Brexit or in favour of a second referendum. The rest of the vote for pro-Remain parties is dispersed relatively evenly between Change UK, the Greens, and the Liberal Democrats. Beyond the EU elections, the question is whether this fragmentation of the vote will have a more lasting impact on British politics and provide a launchpad for pro-Brexit and pro-Remain parties.

The EU elections will also have a much more immediate effect on UK politics by sending a signal to British MPs about how the electorate feels about Brexit. The British Parliament remains in deadlock over Brexit, with a majority of MPs opposed to the Prime Minister’s deal with the EU. Parliament has also expressed opposition to leaving the EU without a deal and to holding a second referendum. So, the question is whether Brexit might make certain MPs rethink their Brexit position, thus shifting the balance in the House of Commons. If Farage’s Brexit Party wins the most seats would this be enough to persuade reluctant Labour MPs to back a withdrawal agreement or it may even persuade more Conservatives that backing a No Deal Brexit is the best way to regain their electoral fortunes? Conversely, if the Remain parties do better than expected, will this put pressure on Labour and some Conservative MPs to back another referendum on Brexit?

A lot is at stake for British politics, but UK MEPs will also take their seats in the European Parliament, and will – at least for a short period – shape the balance of power in the chamber. These EU elections are expected to result in a more fragmented and more polarised parliament than ever before and UK MEPs add to the uncertainty about the balance of power. As the British Labour Party is expected to perform well, this will strengthen the centre-left Socialists & Democrats (S&D) group vis-à-vis the dominant centre-right European People’s Party (EPP), especially since no British MEPs will join the EPP. This may give the S&D a greater say on the distribution of top jobs in the EU.

As a result, British MEPs could have an impact on the institutional make-up of both the parliament and the commission long past their departure. There is also a concern that a strong performance by British anti-EU parties will fortify the rise of the populist Eurosceptic parties in the European Parliament. If the Brexit Party joins forces with Salvini’s and Le Pen’s national populists, this grouping could be one of the strongest in the parliament. This prospect may indeed make European leaders more reluctant to countenance further extensions to Britain’s membership of the EU if a solution to Brexit is not found before the October deadline.