After months of debate and argument among Turkey's opposition parties, all sides united on Monday and named the head of the main secular party as their joint candidate against President Recep Tayyip Erdogan in the May 14 polls.
Republican People's Party (CHP) chief Kemal Kilicdaroglu said he would name the popular mayors of Istanbul and Ankara as vice presidents should he end Mr Erdogan's two-decade rule, to avoid a split of the opposition vote.
"We would have been eliminated had we split up," Mr Kilicdaroglu, 74, told huge crowds of cheering supporters after emerging from hours of tense talks.
Mr Erdogan, 68, faces the fight of his political life in what many regard as Turkey's most consequential election since its birth as a post-Ottoman republic 100 years ago.
He needs to overcome the hurdles of an economic crisis and the aftermath of a devastating earthquake as he seeks to extend his Islamist style of rule until 2028.
Opinion polls point to a tight race that remains far too close to call.
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But Mr Erdogan's task appeared to become a little easier when one of the main leaders of the six-party opposition alliance walked out of the talks on Friday.
Meral Aksener said Mr Kilicdaroglu, a soft-spoken member of the long-marginalised Alevi community, lacked the public appeal to defeat Mr Erdogan.
Ms Aksener has instead urged the popular CHP mayors of either Istanbul or Ankara — Ekrem Imamoglu and Mansur Yavas — to step into the race.
The two met Ms Aksener on Monday in a make-or-break attempt to bring her nationalist Iyi Party back into the opposition fold.
"Our nation cannot tolerate a split," Mr Yavas said after the meeting.
The opposition last united in an effort to unseat Mr Erdogan's allies in municipal elections held in 2019.
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Their ability to regain control of Turkey's two main cities shattered Mr Erdogan's aura of invincibility and set the stage for the possible return to power by the party of the secular state's revered founder Mustafa Kemal Ataturk.
But Mr Kilicdaroglu wanted Mr Yavas and Mr Imamoglu to keep their posts to avoid the threat of handing back control of either city to Mr Erdogan's Islamist-rooted party.
A 12-point text out Monday committed Mr Kilicdaroglu to naming the other five party leaders as vice president for a post-election transition period should he win.
Mr Kilicdaroglu would then appoint the two mayors as vice presidents "at a time deemed appropriate by the president".
Party leaders said Ms Aksener made the two appointments her main condition for rejoining the opposition bloc.
"The nation won," Iyi Party deputy leader Bahadir Erdem tweeted after the announcements.
Analysts regarded the opposition's failure to put aside their differences just two months before the vote as one of the main factors working in Mr Erdogan's favour.
His public approval plunged after he unleashed an unusual economic experiment in late 2021 that tried to fight inflation by drastically cutting interest rates.
A resulting currency crisis erased people's savings and pushed the annual inflation rate to 85 per cent.
Turkish stocks and eurobonds rallied on rising investor hopes that the candidate would be able to beat Mr Erdogan and restore economic orthodoxy after years of turmoil.
Mr Kilicdaroglu is now also expected to hold separate talks with the pro-Kurdish HDP — parliament's third-largest party — to see if he can further expand his appeal.
The HDP had been excluded from the opposition talks because of Ms Aksener's more hawkish policy views.
"We embrace the people's desire for change," HDP co-leader Mithat Sancar said after Mr Kilicdaroglu's name was announced.
"The HDP will do its part."
Mr Erdogan's widely praised handling of Russia's invasion of Ukraine helped to reverse the slide in his approval rating and set him up with a chance to secure a come-from-behind win.
But a catastrophic earthquake last month that killed more than 46,000 people in Turkey and nearly 6,000 in Syria threatened his entire political career.
Mr Erdogan conceded that his government had been slow to respond in the first critical days of the crisis and asked voters to forgive him for rescue delays.
He brushed aside rumours that he would try to delay the May vote to a more politically favourable date.
"We are not hiding behind excuses," Mr Erdogan said last week.
He told a weekly cabinet meeting that he would announce the formal start of the election campaign on Friday.
