Voting has begun in Britain and the Netherlands for European Parliament elections in which Eurosceptic parties stand to be the likely beneficiaries of a disillusioned and apathetic electorate.
After two months of campaigning that opinion polls suggest has largely failed to inspire the electorate, up to 380 million Europeans will vote in 28 countries, choosing 751 deputies to represent them in the European Parliament.
In Britain, the UK Independence Party, which wants tighter immigration controls and to withdraw from the EU, is predicted to win the vote, pushing the governing Conservatives into third place behind Labour, according to opinion polls.
A similar story is expected in the Netherlands, where the anti-Islam and anti-EU Freedom Party - which plans to forge an alliance with France's far-right National Front - is expected to win with up to 23 percent of the vote.
The Netherlands will release exit polls on Thursday evening, but Britain will only announce its results late on Sunday, once voting has finished in all EU member states.
Consolidated results, including the allotment of seats in the parliament, will be announced at around 2100 GMT on Sunday.
The bulk of countries will vote on May 25, when the trend towards the political extremes may become clearer, particularly in France, Denmark, Hungary, Italy and Sweden.
On the last day of campaigning, Jean-Claude Juncker, the top candidate for Europe's centre-right political group, urged people to vote, but not to throw their votes away.
"Do not give your votes to extremist xenophobes or fascists," he said at a rally in Brussels.
"If you want Europe to function and to serve its citizens, we should vote for people who will work hard in the next European Parliament."
Since the first direct elections to the European Parliament were held in 1979, turnout has fallen every time, dropping to 43 percent in 2009. That is expected to continue, falling to about 40 percent this year, pollsters say, a factor that will tend to boost the vote for radical parties.
Despite dwindling turnout, Europe's mainstream political groups - the centre-right European People's Party, the centre-left Socialists & Democrats, the liberal ALDE alliance and the Greens - are together expected to secure 70 percent of the vote, leaving them as a driving force in Europe as long as they work together.
While the European Parliament has in the past been derided as a toothless talking shop, it has gained relevance since the passage of the Lisbon Treaty in 2009 and now enjoys "co-decision" powers with member states over most legislation.