A record number of police were to be deployed for the parliamentary elections - the fifth in Macedonia since it gained independence from the former communist Yugoslavia in 1991.
Outgoing Prime Minister Nikola Gruevski called the polls hoping to secure an absolute majority for his centre-right VMRO-DPMNE after a crisis in his fragile ruling coalition hampered its work on several fronts.
Surveys suggest a solid win for VMRO-DPMNE, ahead of the main opposition Social Democratic Union of Radmila Sekerinska, 35, and two ethnic Albanian parties that have blamed each other for the pre-poll violence.
But Gruevski, 37, is again likely to need the support of the Democratic Party of Albanians (DPA), or their fierce rivals, the Democratic Union of Integration (DUI), to cobble together a government.
The DPA withdrew its support for his government in mid-March, protesting its failure to recognise Kosovo, a neighbouring Albanian-majority province of Serbia that declared its independence the month before.
That stalled the Gruevski government's efforts to continue with integration into the European Union.
Macedonia won EU candidate status in 2005. However, the political turmoil, Albanian tensions and corruption have meant the 27-nation bloc has yet to set a date for the start of membership talks.
Adding to the political turmoil was Greece's veto in early April of an invitation for Macedonia to join Nato, which along with European Union membership, was the government's main strategic goal.
Athens made the move because of a long-running row over the right to the name Macedonia, which is shared by a Greek province. Macedonia was admitted to the United Nations in 1991 as the Former Yugoslav Republic of Macedonia, or FYROM.
The polls will be observed by some 13,000 police, including rapid reaction and helicopter units, and more than 6,200 monitors, among them 464 from the international community.
The elections are seen as a yet another test of the tiny, landlocked Balkan state's political maturity.
The campaign got off to a violent start, however, with the opposition Albanians accusing those in power of being behind attacks on 10 of its regional offices, and the May 12 "assassination attempt" on its leader, Ali Ahmeti.
But the DPA headed by Menduh Thaci hit back, saying the shooting was merely a pre-poll stunt by DUI.
Voting by the electorate of almost 1.8 million started at 7am, and is to continue for 12 hours at nearly 3,000 polling stations across the country.
The State Electoral Commission is expected to start giving its preliminary results from around 10pm.