Istanbul Mayor Ekrem Imamoglu hailed the victory, which dealt a blow to the Turkish president's standing after two decades in power.
Turkey's main opposition party has claimed victory in local elections in Istanbul and Ankara, inflicting the biggest defeat on President Recep Tayyip Erdogan and his Justice and Development Party in more than two decades.
With more than 95 percent of ballot boxes open in Istanbul on Sunday, Istanbul Mayor Ekrem Imamoglu, of the Republican People's Party, said he defeated Erdogan's ruling Justice and Development Party candidate by more than a million votes.
“Those who do not understand the nation's message will lose in the end,” Imamoglu, a former businessman, told thousands of supporters late Sunday.
“Tonight, the 16 million citizens of Istanbul sent a message to our competitors and the president.”
In the capital, Ankara, Republican People's Party Mayor Mansur Yavaş announced victory over his rival, praising the result as a “clear message to those who rule this country.”
The CHP was also ahead in Izmir, the third city in Türkiye.
In all, the CHP controlled in 36 of Turkey's 81 provinces, the state-run Anadolu news agency reported, leading to its success in many AKP strongholds.
Opposition supporters gathered in Istanbul to celebrate the results, with tens of thousands of people lighting torches and waving Turkish flags.
In a speech from the balcony of the presidential palace, Erdogan, who has ruled Turkey since 2002, acknowledged that his party had “lost ground” across the country and said he would review itself and correct any mistakes.
He said: “We will correct our mistakes and correct our shortcomings.”
In the previous local elections in 2019, Imamoglu won the Istanbul mayoral race, dealing Erdogan and his Justice and Development Party the biggest electoral blow to that point. This defeat also marked a personal note for Erdogan, who was born and raised in the city and served as mayor in the 1990s.
The local elections that took place on Sunday represent a new blow to the president, who had his sights set on regaining control of these urban areas.
About 61 million people are eligible to vote for mayors across Turkey's 81 provinces as well as provincial council members and other local officials on Sunday.
Analysts and civilians considered the local elections nationwide as a measure of support for Erdogan and the strength of the opposition amid rising inflation and the collapse of the Turkish currency against the dollar.
Sinan Ulgen, director of the Istanbul-based Edam Research Center, told The Associated Press that the “surprise result” was the result of voters’ desire to punish the ruling party because of the state of the economy and described the election as “a turning point for Imamoglu.” “.
“He will emerge as a natural opposition candidate for the next round of presidential elections,” Ulgen said.
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