The people of the Netherlands go to the polls today to vote on the European constitution today with polls pointing to a resounding "No" that would compound the crisis of confidence in the bloc triggered by France's rejection of the treaty at the weekend.
Most mainstream Dutch parties from right and left have campaigned for a "Yes" vote but opinion polls
A woman in Amsterdam pushes a baby stroller past an anti-EU constitution poster
give the "No" camp a huge lead, with opposition to the treaty rising in most surveys since the French shunned the charter on Sunday.
Polling stations opened at 0530 GMT for the more than 12 million Dutch eligible to vote and will close at 1900 GMT, when a national exit poll is due to be published.
Interim results are expected after about half of votes cast have been counted around 2000 GMT. The final outcome is expected around midnight.
Support for the European Union in the Netherlands, like France one of the bloc's six founding members in the 1950s, was traditionally strong but has taken a knock in recent years against a backdrop of rising political and social tensions.
Opposition to the treaty has been driven by a plethora of issues ranging from deep Dutch dislike of the euro, fears of a loss of control over immigration, opposition to Turkey's bid to join the bloc and concerns Brussels might undermine liberal Dutch policies on gay marriage, soft drugs and abortion.
"It would be a miracle if a majority of the Dutch population said 'Yes'," said pollster Maurice de Hond.
Supporters of the treaty have warned the Netherlands risks isolation in the EU if it votes "No" and says the treaty will enhance Europe's voice in world politics and help the continent face up to growing economic competition from Asia.
After the French "No", most EU leaders ruled out renegotiating the treaty and said ratification should continue, noting that nine countries representing almost 49 percent of the 454 million EU citizens have already approved it.
A Dutch "No" is likely to make that position less tenable and EU leaders will consider the situation at a summit on June 16-17. Britain could call off its referendum planned for next year but is likely to wait for agreement with other EU leaders.
The treaty, designed to make decision-making easier after the bloc's enlargement from 15 to 25 member states last year, needs the approval of all members to go into force. Without it, the EU would continue to operate under rules designed for a smaller union that could paralyse the enlarged bloc.
A Dutch rejection of the treaty could also cast doubt on the further enlargement of the EU to the western Balkans, Turkey and Ukraine and raise doubts about the bloc's economic policy, weighing on the euro and on eurozone government debt prices, which have both slipped since the French "No".
A "No" vote would mark the latest milestone in a period of unprecedented turmoil in usually staid Dutch politics since the 2002 murder of anti-immigration populist Pim Fortuyn.
Fortuyn stoked anti-establishment anger and Dutch fear of immigrants, particularly Muslims, that was further fuelled by the murder of a filmmaker critical of Islam six months ago.
Rising unemployment and budget cuts have also pushed public trust in Prime Minister Jan Peter Balkenende, in power since 2002, to a record low.
France's "No" cost the prime minister his job but Balkenende has ruled out resigning after a "No" vote and said it is up to parliament to decide how to proceed as it called the vote against his wishes. The next general election is due in 2007.
The Dutch vote is not legally binding. Under Dutch law only parliament can accept or reject the constitution and lawmakers will still have to vote on the treaty. But political parties and government ministers say they will follow the wishes of the electorate, as long as voter turnout is more than 30 percent.
Balkenende has declined to comment on suggestions the country might hold another referendum next year if most other EU states approve the treaty, but has noted that had happened in Denmark and Ireland after voters there rejected EU treaties.