Tunisia's President Kais Saied, seen as a saviour by supporters and an autocrat by critics, is running for re-election on Sunday in a vote that he is all but certain to win.

More than a dozen politicians had hoped to challenge him, but the electoral commission approved only two additional names for the ballot paper.

And one of those, Ayachi Zammel, was sentenced to 12 years in prison for falsifying documents just five days before the poll.

Tunisia was where the Arab Spring, a series of uprisings against autocratic rulers in North Africa and the Middle East, began in late 2010. The country was seen as a beacon of democracy for the Arab world.

But since President Saied was elected on a wave of optimism in 2019, the 66-year-old has suspended parliament, rewritten the constitution and concentrated power into his hands.

This is Tunisia's third presidential election since Zine al-Abidine Ben Ali was overthrown in 2011. He had been in power for over two decades before he was forced to flee to Saudi Arabia following months of massive protests.

Sarah Yerkes, a senior fellow at the Carnegie Endowment for International Peace with an expertise in the Middle East, told the BBC, that the president had "manipulated the political and legal situation to such an extent that there is no contest – he is the only viable candidate".

There have been no campaign rallies or public debates, and nearly all the campaign posters in the streets have been of the president.

Tunisia's election was "really a referendum on Kais Saied", Ms Yerkes added.

The North African country’s largest opposition party, Ennahda, said its senior members had been arrested at a level it had not seen before.

New York-based group Human Rights Watch reported that the authorities had excluded eight other prospective candidates from the election through prosecution and imprisonment.

In recent weeks, people have taken to the streets of the capital, Tunis, to protest against President Saied and demand free-and-fair elections.

Although Zammel, who heads the small liberal Azimoun party, was jailed for falsifying voter signatures on his candidacy paperwork, his name will still appear on the ballot paper.

He has denied the charges, the Reuters news agency reports.

The other candidate, former lawmaker Zouhair Maghzaoui, had been a supporter of the president's 2021 power grab but later became a critic.

“Tunisian authorities are waging a clear pre-election assault on the pillars of human rights," said Agnès Callamard, the secretary-general of rights group Amnesty International.

Ms Yerkes told the BBC that Tunisia's leader had "steadily dismantled a decade-worth of democratic progress".

But he was initially seen in a very different light.

When Saied, an acclaimed legal scholar, won more than 70% of the presidential vote in 2019, he promised “a new Tunisia”.

He represented "the non-elite in Tunisia" and tried "to be a voice for the more marginalised populations", said Ms Yerkes.

A rejuvenated economy and curbing corruption were a few of the promises he made after his victory.

When asked what he would do about the economy, he told a local newspaper, he would "empower the people with tools". He did not specify what these tools would be.

Nicknamed “the professor”, he had immense support, especially among young people disillusioned by the endless bickering of the political classes.

But in 2021, he initiated what experts describe as a “self-coup” when he dismissed parliament and assumed all executive power.

He justified his actions by saying he needed new powers to break the cycle of political paralysis and economic decay.

That same year he denied having any autocratic aspirations in an interview with the New York Times when he quoted the former French President Charles de Gaulle saying: "'Why do you think that, at 67, I would start a career as a dictator?'”

Under Saied's rule, Tunisia has dropped from 53rd place to 82nd on the Economist Intelligence Unit's democracy index, which measures political freedoms and pluralism.

“He has already returned Tunisia to autocracy,” said Ms Yerkes.

In addition to Tunisia's faltering democracy, the lack of jobs is another hot topic. Unemployment is at 16%, according to the World Bank.

The country's troubled economy has forced many young people to emigrate.

Tunisia is a key departure point for migrants who want to reach Europe.

UN figures show that at least 12,000 migrants who landed on Italy's shores last year left from Tunisia.

Fearing a further influx of migrants, the European Union made a deal with Tunisia, giving the country $118m (£90m) to stop smuggling, strengthen borders and return migrants.

Saied has also taken a populist approach to stoke support and blamed migrants for the country's economic problems.

He accused black sub-Saharan migrants of partaking in a “plot” to change the country's demographic profile, blaming “traitors who are working for foreign countries”.

This led to a spate of racist attacks against black people living in Tunisia.

While his rhetoric has garnered him some support, there are those who have been turned off by the remarks.

Groups in the country organised anti-racist protests in response to his comments.

He has attempted to shift blame but has “shown no signs that he can turn the economy around”, said Ms Yerkes.

In his first electoral statement, published just after official campaigning began, Saied pledged to strengthen health services, transport and social security after decades of efforts to "eliminate" public institutions.

Saied's consolidation of power has led to an apathetic mood ahead of the elections.

Last year, only 11% of the electorate turned up to vote for new members of parliament.

It is “likely that the turnout this time around will be similarly abysmal”, said Ms Yerkes.

The official results will be announced within three days of the election but the outcome is hardly in doubt.