Analysts were considering on December 15 whether the Erdogan regime may have haplessly anointed a candidate well placed to defeat strongman Recep Tayyip Erdogan in Turkey’s 2023 presidential election given outrage at the actions of a judiciary that have raised the national profile of the potential challenger, Istanbul mayor Ekrem Imamoglu.

The day saw thousands of people rally in Istanbul to denounce the conviction, prison sentence and political ban handed to Imamoglu on December 14, a man they hope will prove Erdogan’s nemesis. They voiced their anger at Erdogan and his ruling AKP party for what critics home and abroad have described as an abuse of democracy, at one point chanting: "Rights, law, justice. ... The day will come when the AKP is called to account."

Patriotic music played and the crowd waved Turkish flags in front of Istanbul's municipality building, draped with a huge portrait of Mustafa Kemal Ataturk, the founder of the Turkish Republic.

"The government is afraid and that's why there was such a verdict. Nobody can stop this nation," Filiz Kumbasar, 56, who travelled to the rally from Duzce, a town 200 kilometres (125 miles) from Istanbul, told Reuters.

Confirmation of an appeal from Imamoglu against the verdict was expected.

Imamoglu, a politician whom polls have already shown would likely dislodge Erdogan from the presidency should he be nominated to run against him in the election due by June, was sentenced to more than two-and-a-half years in prison for insulting public officials in a speech with the word “fools”. His conviction, if not overturned, would disqualify him from taking part in the presidential contest.

Erdogan, once described as an “autocrat” by Joe Biden as he challenged Donald Trump for the presidency, remains in trouble in the opinion polls, given that he is widely seen as having plunged Turkey into a longstanding deep economic crisis through economic mismanagement, while dismantling the basic human rights of many Turks.

Responding to the court verdict against him, Imamoglu said: “We will not bow down to this corruption. These kinds of games won’t get in my way—I won’t be dismayed or give up.”

The name of 52-year-old Imamoglu comes up frequently as anti-Erdogan Turks discuss which politician from the six-party opposition alliance—led by Imamoglu’s party, the main opposition Republican People's Party (CHP)—should be nominated as the challenger to Erdogan, who has ruled for nearly two decades. Two other potential candidates are the CHP mayor of Ankara Mansur Yavas, whom some polls have shown would stand an even better chance of unseating Erdogan than Imamoglu, and the long-time head of the CHP, veteran politician Kemal Kilicdaroglu. The latter has sent clear signals that he wants to run but many critics see him as a lacklustre campaigner.

"Yesterday's verdict shows Imamoglu is Erdogan's least favourite rival," Berk Esen, an assistant professor of political science at Istanbul's Sabanci University, was cited as saying by Reuters, adding: "The opposition parties and their electorate will start pressuring towards an Imamoglu candidacy."

Erdogan and Imamoglu entered into a spat after Turkey’s spring 2019 local elections. In a stunning victory, Imamoglu defeated the Erdogan-endorsed candidate to win the Istanbul mayorship. Aides of Erdogan, a former Istanbul mayor himself, responded by vigorously complaining to the Supreme Election Council of irregularities at the polls. A repeat election was called. Imamoglu won it by a landslide.

Months after his victory, Imamoglu voiced the words that landed him in court, when he said: “Those who cancelled the election on March 31 are the fools.” The comment was taken by officials as an insult against election board judges. Imamoglu defended his use of the word "fools" to describe those who overturned the election result, saying he was responding to similar language used by Interior Minister Suleyman Soylu.