|Some 50 million Turks were eligible to vote in the general elections to shape the 550-seat parliament [EPA]
The Turkish prime minister, Recep Tayyip Erdogan, appears on course to secure a third term in office, as results in parliamentary electons show the ruling Justice and Development Party (AKP) with an overwhelming lead.
However, the party looked set to fall short of its target of a two-thirds majority in Sunday's parliamentary vote.
With 95 per cent of votes counted, AKP's share was 50.4, while those of the two main opposition parties, the secularist CHP and the nationalist MHP, respectively stood at 25.8 and 13.1.
The MHP managed to achieve a large enough share of the vote to be elected to parliament. Under Turkey's electoral system, a party must gain at least 10 per cent of the national vote to win seats in the National Assembly.
Erdogan hopes to rewrite the country's constitution after the elections, and a two-thirds majority would have allowed his party to do so unilaterally, without the support of other parties or the need for a referendum.
He says a new referendum is needed to make Turkey more democratic and to enhance individual freedoms.
But opponents say the AKP would write the constitution to consolidate its grip on power, and claim Erdogan wants to introduce a system with more executive powers for the president.
The AKP had aimed to build on economic and diplomatic advances in recent years and set its sights on winning a two-thirds majority of 367 seats that would enable it to rewrite the country's constitution.
Earlier on Sunday, an ecstatic crowd burst into cheers and applause as Erdogan arrived to vote in a school in Uskudar, an AKP stronghold in the Asian part of Istanbul.
"Turkey is proud of you," the crowd chanted as Erdogan shook hands with supporters.
"I've been informed that voting is taking place in a quiet atmosphere across the country ... with a very high turnout," he said.
"Everybody should respect the outcome."
'End of long marathon'
Kemal Kilicdaroglu, the leader of the main opposition Republican People's Party (CHP), voted in the capital, Ankara.
"We have come to the end of a long marathon," he said. "Today is the time for a decision by the people. We will respect their decision. There is a good mood. There is a democracy feast."
The CHP had built its election campaign on pledges of democratic reform, arguing that the AKP is turning Turkey into a "police state."
Sex tapes forced 10 leading members of the MHP to quit the election race.
Candidates from a total of 15 parties, as well as many independent candidates, were in the fray.
Al Jazeera's Mohamed Vall, reporting from an Ankara polling station, said that hundreds of people voted on Sunday morning.
"We can see how much enthusiasm there is for voting, even among the elderly," he said.
Our correspondent said there was some polarisation between different factions within Turkish society, as was always the case in the country.
"But this is the first election perhaps in the history of Turkey where the main paradigm has shifted from ideology to practical matters, like economy, like reducing poverty, like the rights of minorities," he said.
Voters cast their ballots in transparent plastic boxes, rather than traditional wooden boxes, for the first time - a measure introduced to prevent allegations of fraud.
Istanbul will be represented by 85 deputies in the new parliament, while Ankara gets 31 seats. Many of Turkey's less populated provinces will be represented by a single deputy.
Seats are awarded on the basis of proportional representation, with each party gaining a number of seats in each district based on its share of the local vote.
Almost 85 per cent of eligible voters participated in the last elections in 2007.