Hungarians were slow to vote on Sunday in a referendum granting dual citizenship to millions of their compatriots living abroad, with turnout low half-way through the poll that has stirred emotions at home and abroad. Supporters of the proposal say it could heal the hurt of a nation which lost two-thirds of its land after World War One, while critics say a "yes" would be backward-looking for a modern European Union state - as well as costly.
Neighbouring Romania fears Hungary would grant citizenship to Romanians.
"The mother country needs its minorities and this is a moral issue above the financial ones," said 67-year-old Joszef Major, who cast his ballot early Sunday.
Hungarians will also vote on Sunday on an end to hospital privatisation.
The citizenship vote has pinned Prime Minister Ferenc Gyurcsany and his Socialist party, who oppose dual citizenship, against ex-premier Viktor Orban and the opposition Fidesz, who said a yes vote would heal the wounds of a split nation.
If lost, the result threatens to strip Gyurcsany, elected just two months ago, of much of his power to control the domestic political agenda.
The referendum on citizenship also threatens to sour Hungary's relations with its neighbours, especially Romania, which has voiced concern over the possibility that Hungary would grant citizenship to some Romanians.
Polls close at 7 pm (1800 GMT) and preliminary results are due about 9 pm (2000 GMT). By 3 pm (1400 GMT) only 24.7 percent of eligible voters had cast their ballots. That was below the 27.9 percent recorded by 3 pm in a referendum last year on whether Hungary should join the European Union.
In that vote, overall turnout was 45.6 percent.
The plebiscite will only be valid if 50 percent of eligible voters turn out or, if less, at least 25 percent of the 8 million electorate vote either "yes" or "no".
The Socialists say the vote could mean an influx of poor immigrants and a major expense for the budget.
"I am afraid those who would come here are the poorer ones who live in poor conditions in places like Romania where it is difficult to live," said Regina Urban, 27.
An overwhelming majority are expected to vote for halting the privatisation of health care institutions.