Vote on presidential impeachment
Romania's unpopular president is fighting for his political life as the country votes on whether to oust him.
The referendum is part of a political battle which has raised questions about the rule of law in the fledgling European Union member.
Early indications were that he might keep his job due to a low voter turnout.
Traian Basescu's rivals in the government are seeking to push him out for the second time in five years. They claim the 60-year-old populist violated the constitution by meddling in government business, favouring cronies and using the secret services against enemies.
Basescu, a former ship captain whose popularity has plummeted over economic challenges, claims he is the victim of a political vendetta and has urged his supporters to boycott the vote - a tactic which may help him survive thanks to a rule requiring turnout to be more than half of the total electorate.
Three hours before polls were to close, the turnout was just 37.67%, according to the Central Election Bureau. That figure was lower than June local elections when the turnout was about 56%. Some 18 million Romanians were eligible to vote in Sunday's poll, including many living abroad.
Mr Basescu said: "I have done my duty as president in a manner that sometimes pleased people and at other times did not please a large number of Romanians."
Critics accuse Prime Minister Victor Ponta, himself the subject of a plagiarism scandal, of orchestrating the move to oust Mr Basescu as part of a power grab
The political turmoil has dented Romania's credibility with the United States and European Union expressing doubts about the left-leaning government's respect for the independence of the judiciary.
Jose Manuel Barroso, president of the European Commission, the EU's executive branch, last week issued a stern statement expressing "serious concerns about recent political events in Romania in relation to the rule of law, the independence of the judiciary and the role of the Constitutional Court".