Today’s European Parliament election is being billed by some in the U.K. as a proxy second referendum on Brexit.

Many voters, particularly those who feel strongly on either side of the argument, will no doubt use the poll to make their voice heard — particularly by voting for parties with a clear Brexit message.

Nigel Farage’s Brexit Party has pitched the poll as a vote for democracy and against “betrayal.” Meanwhile, his old party UKIP has invited voters to “Tell them again.”

On the pro-Remain side, the Liberal Democrats, Change UK and Green Party are running stridently pro-EU campaigns with calls for a fresh referendum. Change UK has gone one step further and wants Article 50 to be revoked.

But both sides are cautious about portraying today’s vote as a stand-in for a people’s vote/confirmatory referendum/second referendum (delete as appropriate).

Even the Brexit Party — which poll projections suggest will win the contest by a big margin — won’t do that, says one official.

If he wins, Farage will declare the victory as a judgement on the “political class” — the government and the Labour Party — not victory in a de facto referendum, the official said.

The reticence stems partly from the fact that neither side will be able to claim an outright victory. The Brexit Party and UKIP vote tally is unlikely to reach 50 percent, and the pro-Remain caucus will likely be even further off a majority.

The Conservative Party and the Labour Party still have loyalists despite their Brexit woes, and their voters don’t fall neatly into either box.

And there are other important differences too. The question on any future referendum would be crucial. Would there be two options on the ballot paper or three? Would no-deal be included? That makes it hard to map the result onto a second referendum.

And it is widely accepted that only a referendum on Brexit could permit the government to abandon the U.K.’s departure from the EU — the European election won’t change that.

In truth, both sides will likely take the result as vindication of their stance. Brexiteers will argue it backs a swift exit, while Remainers will say only a people’s vote can end the political impasse.

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