ISTANBUL • Soft-spoken football fan Ekrem Imamoglu has emerged from relative obscurity to win Turkey's biggest city - twice - as the new figurehead of the country's long-suffering opposition.

It has been a roller-coaster year for the 49-year-old who shocked most observers by squeaking to victory in Istanbul's mayoral election in March, only to see that result annulled by the election authorities a few weeks later.

He rejected claims by President Recep Tayyip Erdogan that the election had been marred by fraud, saying the ruling party had simply refused to cede control of the metropolis and its vast resources.

The sense of injustice did wonders for Mr Imamoglu's profile at home and abroad, with his Twitter following soaring from 350,000 to more than 2.75 million.

Born in 1970 in the Black Sea coastal city of Trabzon in north-east Turkey, Mr Imamoglu was a little-known district mayor in the western suburb of Beylikduzu, where he had built a reputation as a competent but unflashy administrator.

Mr Imamoglu studied business management before entering his family's lucrative real estate and restaurant business in western Istanbul.

A practising Muslim, he is passionate about football, having played at amateur level, and is still serving on the board of his hometown Trabzonspor team.

The key to his success has been his positive campaigning style - compared to the often vicious personal attacks of Turkish politics - and easy rapport with people on the street, where he is often seen taking selfies with voters in bazaars and cafes.

Mr Imamoglu's marketing has been astute, especially his choice of a slogan for the new campaign - "Everything will be fine" - which came from a 13-year-old boy who ran after his election bus shouting the line. It came to epitomise his style of campaigning, and has caught on with businesses and artists who have often been fearful of challenging the ruling party in the past.

Mr Imamoglu himself remains coy about his future prospects. "Time will tell," he said when asked if he might follow Mr Erdogan's path from the Istanbul mayorship to national leadership.