If Sunday's parliamentary elections really are a battle for the heart of Serbia, then who better than a cardiologist to be one of the leading figures in the race.

Ilija Srdanović appears an unlikely opponent for Serbia's long-serving leader, Aleksandar Vučić, arriving for an interview by motorbike sporting a fluorescent yellow jacket emblazoned with pro-student slogans.

He has been selected as top candidate for an opposition movement posing the most serious challenge to Vučić since the Serbian Progressive Party (SNS) entered government in 2012.

The Student List has emerged from almost two years of anti-corruption protests led by young Serbians, outraged by the deaths of 16 people when a railway station's canopy collapsed in Serbia's second city Novi Sad.

Instead of running for office themselves, student-led assemblies at the country's university faculties have chosen 250 candidates to stand in the parliamentary election, with Srdanović, professor at Novi Sad University, heading the list.

"It is absolutely normal to stand with my students to help them in their fair struggle," Srdanović told the BBC.

The Student List is up against a Serbian leader who has served successively as deputy prime minister, prime minister and president since 2012. When he called these snap elections last month he stood down as president to run again for the role of prime minister.

Whatever Vučić's title, there has never been any doubt that he was the man in charge – an image enthusiastically promoted by Serbia's largely uncritical media.

He retains strong support among a significant section of Serbia's population. They view him as a strong leader who stands up for the country's interests. He can also point to significant economic growth over the past decade and numerous improvements in infrastructure.

Vučić has painted the student movement as foreign-backed and seeking to "bring down our state". "Let us always protect and defend it," he told supporters at a final campaign rally.

Just like the protest movement from which it developed, the Student List has no hierarchy or nominated leader. This makes it a proposition unlike any other in Serbia's relatively short democratic history.

Reliable polls are thin on the ground, but analysts are predicting an extremely tight vote.

Ilija Srdanović may head the list of candidates – but he is not the movement's leader and would not necessarily be first choice prime minister if they won.

Srdanović insists that the Student List has a clear vision: "We offer to our citizens the core values of civilised society, which this previous regime has taken away from our citizens for the last time." The other candidates on the Student List range from academics to athletes – and economists to engineers. None of them has a political background. But the students who selected them believe that is a strength, rather than a weakness.

"We've gathered people who are actually the best in their fields, and we really think that they are competent enough to rule the country," says Aleksandra, a student at Novi Sad University who only wants to give her first name.

"All of them are gathered around the same vision of a country where the freedom of speech is ruling, where you can walk to your home in the middle of the night and you will not be beaten up by some hooligans," she adds.

The Student List and its supporters say that Aleksandar Vučić and the SNS dominate state institutions and media coverage.

At the last parliamentary election in 2023, the International Election Observation Mission noted "overwhelming ruling party advantage" due to "bias in the media" and "misuse of public office and resources".

The BBC approached leading figures in the SNS for an interview but was not offered a response.

For the past 18 months, there has also been a full-time, pro-SNS camp in the small park between the National Assembly and the Presidency building in the centre of Belgrade. Its residents have repeatedly attacked journalists and made the park a no-go zone for local people.

Vučić has called the camp "a symbol of resistance" against those who "cannot stand different opinions". But his major challenge remains what happened outside Novi Sad railway station two years ago.

The station's renovation was a key part of his signature infrastructure project – the high-speed line linking Belgrade and Budapest. So it has been difficult for Vučić to distance himself from the disaster.

Protests followed, with participants accusing the authorities of corruption and having "blood on their hands".

"This is a problem for the government," says Magda Anastasijevic, the Eastern Europe analyst for the conflict monitor, ACLED.

"Vučić has survived this in the past, he was always able to find a scapegoat and blame whatever problems on them. This was not the case for the canopy." On the diplomatic front, he has performed a delicate balancing act.

Membership talks with the EU continue, albeit fitfully, even as Serbia retains close ties with Russia and China – both countries that refuse to recognise Kosovo's unilateral declaration of independence from Serbia. Vučić has warned those links could be severed if the Student List took power.

"When you ask them: will you impose sanctions on Russia? Silence, umming and ah-ing, but no answer," he told the audience at a pre-election rally.

"You know what the Chinese think, you've heard what Vladimir Putin said. So you decide. Think about who has our best interests at heart." The final rallies of the campaign saw the SNS stage an event at Belgrade Arena, with Aleksandar Vučić as the only speaker. But on the other side of the Sava River, the Student List attracted a reported 150,000 people in Slavija Square to listen to a mixture of students and candidates.

The contrasting visions were clear to see: the strong, sole leader – or a collective approach. Now Serbia's electorate must decide which they prefer.