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When President Recep Tayyip Erdogan lost a local election here back in March, he decided to gamble. Citing claims of fraud and widespread irregularities, he and his party pushed for a re-run and the country's high electoral council agreed. That election took place on Sunday and it backfired spectacularly for President Erdogan.
Ekrem Imamoglu, the opposition challenger who had fought the contest the first time round, not only won again, but he increased his majority to about 800,000 votes. The symbolism of Imamoglu's victory for the Turkish opposition is huge. President Erdogan has basically dominated this country's politics for the last 17 years and the opposition have really struggled to make inroads.
Now they're in control not only of Istanbul, Turkey's largest and most prosperous city, but also a string of other cities across the country. Losing Istanbul in particular is very painful for Mr Erdogan. He himself began his own political career here 25 years ago when he won election as mayor of Istanbul.
He often touts his policy that whoever loses Istanbul loses Turkey. Losing Istanbul also has practical significance for Mr Erdogan. It's the richest city in Turkey with the largest GDP and it has a huge municipal budget of around $4bn a year.
Losing that means losing a very rich source of patronage that has helped sustain the party structure over the years. And although it's very early days, many opposition supporters, who were dancing in the streets here last night, now hope that this is the beginning of a new chapter for them and for their hopes and aspirations for Turkey.
