Istanbul will vote for a mayor for the second time in three months on Sunday as President Recep Tayyip Erdogan's party fights to win back the city after a shock defeat in March.
The ruling Justice and Development Party (AKP) successfully challenged the result in the city following the vote three months ago, which saw it lose control of both Istanbul and the capital Ankara for the first time in years.
The man who won the first time around, former district mayor Ekrem Imamoglu of the opposition Republican People's Party (CHP), has grown from little-known outsider to household name since being stripped of his victory over claims of election irregularities.
He will again face the AKP's Binali Yildirim, an ex-prime minister, who lost by around 13,000 votes in the first vote.
The March 31 election showed the Islamic-rooted AKP remains the most popular party in Turkey, but an economic slowdown has eroded its support in metropolitan areas and it lost by a landslide in Ankara.
Having overseen huge growth since taking power in 2003, Mr Erdogan's reputation as an economic strategist has taken a beating in recent years amid double-digit inflation, slowing growth and rising unemployment.
The AKP only challenged the Istanbul mayoral vote, leading to the country's top election authority ordering the controversial re-run.
Mr Erdogan's claims of fraud and "serious corruption" have been denied by the opposition and activists.
They say the AKP is desperate to keep control of the city's huge resources, which are crucial to oil the party machine.
Analysts warn Mr Erdogan is in a "lose-lose" situation on Sunday, since a victory would leave him open to opposition claims that he stole the election.
The re-run has also infuriated voters by forcing them back to the polls for the eighth time in just five years.
The controversy may explain Mr Erdogan's relative silence during the latest campaign.
Mr Erdogan, himself a former Istanbul mayor, was the face of the local elections in March, rallying tirelessly for months across the country and portraying the vote as a matter of national survival even though he was not running.
At one point he made eight appearances in a single day.
This time: hardly any rallies, no big television interviews, and comments which appear to suggest the party would not be concerned if the opposition won.
Last weekend, he dismissed the Istanbul vote as "only a change in the shop window" since the AKP already runs almost two-thirds of the city's districts.
But Berk Esen, assistant professor of international relations at Ankara's Bilkent University, said Mr Erdogan chose not to campaign to avoid becoming "the face of defeat".
"Erdogan is obviously still very popular with many AKP voters but his presence polarises the electorate and mobilises the opposition vote," Mr Esen said.
Mr Imamoglu, 49, has been able to play the victim since being stripped of his mayorship, and has opted for a unifying message that seeks to transcend the usual aggression of Turkish politics.
The kingmakers in the Istanbul vote could be the Kurdish population, who are thought to number around two to four million in the city.
There have been efforts by the ruling party to reach out to the community in recent weeks, with Mr Yildirim visiting the mostly Kurdish city of Diyarbakir.
But the pro-Kurdish Peoples' Democratic Party (HDP) has again thrown its support behind Mr Imamoglu, with jailed former leader Selahattin Demirtas tweeting his support this week, and the party opting not to field a candidate.
Still, it is wise never to bet against Mr Erdogan.
His party has won every national election since 2002.
In 2015 when it lost its overall majority in parliament, snap elections were called and it won it back.
Jean Marcou, associate researcher at the French Institute of Anatolian Studies, said the AKP was seeking to mobilise conservative Kurds, the youth and new voters whom the party believes would vote for them.
Experts have said a loss in Istanbul would chip away at Mr Erdogan's image of invincibility and could lead former AKP insiders to vie for power.
Rumours persist that ex-prime minister Ahmet Davutoglu or the popular former economy minister Ali Babacan could form new parties.
"People in the party will realise it's not an unstoppable electoral machine and it can lose," Ayse Ayata, a professor at Ankara's Middle East Technical University, said.