The poll is the second in only five months, called after the Justice and Development Party (AKP) lost its parliamentary majority in June for the first time in 13 years of single- party rule and then failed to forge a power-sharing government.
Opinion polls are, however, predicting a replay today, leaving the strategic Muslim-majority nation at risk of further instability just as it is facing what some observers warn are existential threats.
Turks are fearful of a return to all-out war with outlawed Kurdistan Workers' Party (PKK) rebels after renewed violence shattered a 2013 truce in July, just a month after a pro- Kurdish party took up seats in parliament for the first time.
President Recep Tayyip Erdogan's Islamic-leaning AKP is tipped to win between 40 and 43 per cent of the vote, paving the way either for a shaky coalition that many analysts say will not last long, or yet another election.
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With the country polarised along ethnic and sectarian lines and its economy faltering, Prime Minister Ahmet Davutoglu called yesterday on voters to choose "stability".
"We will definitely clear Turkey of terror, fighting, violence and hostility. We will never make concessions on democracy, freedom and rights."
The vote could also determine the future of Erdogan, who has dominated Turkey's political scene for more than a decade, even though his name is not on the ballot paper.
The stunning June election setback wrecked - at least temporarily - his ambition to expand his role into a powerful US-style executive presidency that opponents fear would mean fewer checks and balances on a man seen as increasingly autocratic.