Nigel Farage, a member of the European Parliament, attends a campaign event in April.Peter Nicholls / Reuters

Britons are gearing up for what was supposed to be someone else’s election.

For most European Union countries, this week’s elections are an opportunity to elect representatives to the bloc’s legislative body, the European Parliament, for the next five years. For Britain, however, the May 23 vote will take on a decidedly different tone—one in which its voters will select candidates to shape a body that, until recently, many assumed would no longer matter to them because of Brexit. Depending on what happens with the country’s stalled bid to leave the EU (spoiler: No one knows), newly elected British members of the European Parliament could end up taking their seats for weeks, months, years—or possibly not at all.

In an alternative universe, the country would have left the bloc on March 29 as planned. In this universe, however, Parliament has rejected Prime Minister Theresa May’s negotiated Brexit deal with the EU three times. No one knows when, or even if, Britain will leave the bloc. Britons remain hopelessly divided over the best way forward and over which parties can lead them there.

It is for this reason that these European elections, which have in the past been low-priority votes that few turn out for, stand to be consequential. The polls have the potential to give a snapshot of where the public stands on Brexit, nearly three years after the original referendum. It will provide voters the opportunity to voice their frustrations and potentially throw their support behind emerging parties. Perhaps most important for those currently in government in Britain, this vote will signal which voters are most mobilized to turn out in future elections.

Put another way, it will tell British lawmakers who is angriest.

There’s plenty of anger to go around: Those who voted in 2016 for Britain to leave the EU—52 percent—are frustrated that the goal has yet to be realized. Those who voted to remain—48 percent—are angry that Brexit could still happen at all.

If it sounds like this contest is shaping up to be all about Brexit, that’s because it is. Though European elections are ostensibly about electing lawmakers who will shape the EU’s future, they almost always end up being domestic affairs—and no subject is more dominant in British national politics now than Brexit. Paradoxically, the country that is debating the EU most intensely is the country that is set to leave.

The temptation to treat the European elections as a proxy for a second referendum on Britain’s EU membership has already been seized by virtually every party in contention, and the idea appears to be spreading among voters too. A recent survey by the British polling firm YouGov projects that the nascent Brexit Party, which advocates Britain leaving the EU without a deal, could win as much as 35 percent of the vote—higher than the Conservative (9 percent) and Labour (15 percent) Parties combined. The anti-Brexit parties, which include the Liberal Democrats (16 percent), the Greens (10 percent), and the newly established pro-second-referendum party Change U.K. (5 percent), are projected to win a combined 31 percent of the vote.

Most European Parliament candidates I spoke with said that this election was being treated like another Brexit vote, but not all of them think it should be. “It’s a false promise that people will be selling, because we’ve already had a referendum—we’ve already had a decision,” Emma McClarkin, an incumbent Conservative MEP and Brexit supporter who represents England’s East Midlands, told me.

It’s true that victories for the Brexit Party and Change U.K. in the European elections won’t shift the makeup of Britain’s Parliament. For these new parties, though, that hardly seems to matter. To hear them tell it, the point of contesting the European elections is “to build a platform for a general election,” Alexandra Phillips, a Brexit Party MEP candidate for England’s Southeast region, told me. She said a Brexit Party victory in the European election would “send a very clear message back to the political parties in the U.K. about what it is they need to do”: deliver Brexit.

Indeed, neither the Brexit Party nor Change U.K. appears to have any policies apart from Brexit. But both see the European elections as a springboard into national politics. “If we get any seats [in the European Parliament], it will be a triumph,” Gavin Esler, a Change U.K. candidate for London, told me.

Still, converting victory in Europe into success at the national level is far from easy. Just look at the Brexit Party leader Nigel Farage’s former outfit, the U.K. Independence Party: Despite winning the largest share of votes in the last European elections in 2014, it has no seats in the British Parliament. This is due in part to low voter turnout in the European elections and the EU’s proportional-voting system, which, unlike Britain’s winner-take-all national elections, enables smaller parties to perform better. But it also stems from the fact that voters are more likely to lend their support to smaller parties in elections where the makeup of the national government isn’t at stake.

Seb Dance, an incumbent Labour MEP representing London, expressed concern that a new crop of British MEPs who were focused exclusively on Brexit could distract voters from other issues facing the country.

“I don’t get the point of sending people to the European Parliament who are just going to stand there and make speeches denouncing it, which is what they do,” he told me.

As far as the candidates of the new parties are concerned, that will be the point when a new session of the European Parliament convenes in July.

“The big issue that needs to be solved is leaving the European Union,” Phillips, the Brexit Party candidate, said. “That is the only issue in town.”

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