Polls have now closed in Turkish parliamentary elections that are more about the fate of Turkey's long-time leader, President Tayyip Recep Erdogan, than they are about forming a new government.
Preliminary results are not expected to start coming in for some hours.
Nominally, voters were asked to choose 550 members to lead the country's next Grand National Assembly, but behind the scenes Erdogan has been pushing hard to ensure that his ruling Justice and Development Party (AKP) wins a convincing majority in order to push through fundamental changes to Turkey's constitution.
One of those changes would be to shift Turkey to a presidential system -- to be led by Erdogan himself -- from the country's current European-style parliamentary system.
None of the other parties have expressed much interest in the idea and prefer keeping the existing parliamentary structure.
Sinan Ulgen, chairman of the Istanbul-based think tank Centre for Economics and Foreign Policy Studies (EDAM), says Erdogan -- who was elected president in a landslide popular vote in August -- favors a presidential system because it would effectively concentrate more power in his own hands. For Erdogan, Ulgen says, moving to a presidential system would help him "get rid of the existing system of checks and balances" on his authority.
Erdogan, for his part, says Turkey's parliamentary system needs to be replaced because it's holding back economic growth. Under the current parliamentary system, Erdogan's presidential powers are largely symbolic.
Erdogan's AKP party has ruled Turkey with an absolute majority for 13 years and is favored to win the vote, but observers say the expected margin of victory has narrowed in recent weeks. Two numbers will be crucial for Erdogan's and AKP's aims of changing the constitution: 330 AKP seats would allow the party to put the constitutional changes to a national referendum, while 367 seats would enable the party to make direct changes to the constitution within the assembly. Both numbers may now be out of reach.
Currently, AKP holds 311 seats in the parliament, with the main secular opposition Republican People's Party (CHP) presiding over 125 seats. The rest of the seats are distributed among other smaller parties and independents. Parties require a minimum of 10 percent of the popular vote to qualify for a seat.
Analysts cite a number of reasons why Erdogan's popularity and that of the AKP party may be eroding, including rampant claims of corruption, a weaker Turkish economy, and relatively high unemployment. The country's unemployment rate, at around 11.3 percent, is the highest it's been in five years.
In addition, Erdogan's image has been tarnished by the heavy-handed, government-led crackdown on protesters in Istanbul over the proposed destruction of the city's Gezi Park. Part of that crackdown has been the passage of harsh, new laws that, among other things, grant police the right to use live ammunition on protesters and to detain citizens without a court order.
Ulgen says AKP's pursuit of an absolute majority in parliament is threatened by the rapid rise of several smaller parties, particularly the pro-Kurdish People's Democratic Party, HDP, headed by its charismatic leader Selahattin Demirtas.
Under Demirtas, a 42-year-old former human rights lawyer, the Associated Press (AP) writes that HDP has expanded its appeal beyond Turkey's Kurdish regions, attracting leftist and liberal voters in the rest of Turkey. Demirtas told the news agency that many people now consider his party to be the only one that can block "Erdogan's stance of unlimited power." What Erdogan calls "presidency," Demirtas told AP, "We call 'dictatorship.'"
If the HDP manages to clear the 10 percent threshold to enter parliament, Ulgen says that would likely curb AKP's dominance and prevent it from achieving a super-majority.
Ulgen says there are several potential coalition scenarios linking the AKP to other smaller parties or even uniting the major opposition parties against the AKP, in case the ruling party fails to secure enough seats to form a government.
The most likely scenario, Ulgen says, would unite the AKP and the far-right Nationalist Movement Party (MHP). The MHP -- which opposes government-led effort to mediate peace with Kurdish rebels in the east -- has surged in popularity over the past year. In spite of their differing policies over the Kurds, both the AKP and MHP appeal to similar, conservative-leaning constituencies.
Another possibility, Ulgen says, would be a grand coalition between the AKP and the main opposition CHP, but Ulgen says the chances that Erdogan would consider this union are low. For one thing, he says, it would end Erdogan's aspirations to adopt a presidential governing system.
Other scenarios include a coalition uniting all of the leading opposition parties -- CHP-MHP-HDP -- against the ruling party, but this might prove difficult given the wide ideological differences between the MHP and HDP. One variation of this combination would see a union between the CHP and MHP, with backing from the HDP.
AP writes that Erdogan took a big gamble when he announced last year that he would seek the presidency in the country's first direct vote for the largely ceremonial post, rather than lead his party into the election as prime minister, as in previous years. He bet that after moving into the presidential palace, he could make the position powerful with an expanded majority in parliament. That now looks to have been a rare miscalculation for a man who has dominated Turkish politics since his party came into power in 2002.