In Latvia, voters are deciding whether the former Soviet republic should join the European Union. Latvia is the last of 10 proposed new members that would bring EU membership to 25. Opinion polls indicate a win for the "yes" campaign, although many Latvians have their doubts about the benefits of EU membership.
Voting started at an early hour under overcast skies in the small Baltic nation, with recent polls indicating that a victory for the "yes" campaign is likely.
Latvians are traditionally more skeptical of the merits of EU membership than their neighbors in Estonia and Lithuania.
But Latvians have come under increased pressure since two thirds of Estonians approved entry in their own referendum last Sunday.
President Vaira Vike-Freiberga and other top officials also waged a campaign to convince Latvians they must go along with the other nine nations that have already decided to join the EU next May. Most of those countries are in Eastern Europe.
Proponents say membership will bring stability as well as access to lucrative markets and EU development aid to raise living standards in the country.
They also argued that a "no" vote would leave tiny Latvia as the odd-nation out, given the positive votes throughout Eastern Europe. Malta and Cyprus will also join the EU next year.
However, many Latvians remain unconvinced, worried that their small economy will be at a disadvantage in the giant EU bloc.
Early polls showed only around 50 percent of Latvians favored entry. However final polls taken last week indicated that between 55 and 65 percent of the country's 1.4 million voters will probably vote yes.
There are also a lot of doubters in Latvia's sizable Russian-speaking minority accounting for more than one-third of the population.
Almost all of the Russians arrived during the half-century when Latvia was occupied by the Soviet Union. A large number of them cannot vote as they do not have Latvian citizenship.
The status of the Russian minority has long been an irritant in relations with Russia, which has applied economic pressure on the country given the close economic links that were established in Soviet times.
Moscow is also upset by the fact that Latvia is due to join the NATO military alliance next year, along with Estonia and Lithuania.
The country's leaders say if Latvia is able to join the two Western groupings it would guarantee the country's security and full independence from its giant eastern neighbor.