BELGRADE — Despite a warm round of congratulations from EU leaders to Aleksandar Vučić on his presidential victory in Serbia this week, Brussels should be worried about the future of this candidate for membership in the bloc.

It was the promise of prospective EU accession that propelled Vučić’s party into power in 2012. Back then, nearly 70 percent of voters wanted to join the European Union.

Fast forward to 2017 and none of the presidential candidates included EU membership in their campaign pledges. That’s because polls show support for integration has fallen to 43 percent, with 35 percent of my fellow Serbs saying they are against a future in the bloc.

The EU policymakers I work with in Brussels still count on Vučić to guide Serbia into a deeper western embrace, but concern over his courtship of the Kremlin is growing. Moscow has promised to gift Belgrade six MiG-29 warplanes and a collection of tanks and scout vehicles. Presents from Russian President Vladimir Putin always come with a price tag. In this case, we just don’t know what it is.

Yet European leaders still look enviously at Vučić’s enormous election win, with some 55 percent of the vote, and see a stable partner — perhaps one who can finally agree to Kosovan independence.

They need to take a closer look at the results still trickling out. In Belgrade and a few other urban centers, the combined opposition won more votes than Vučić — which is striking, given his increasingly authoritarian command of my country and its media.

Vučić has brought the country’s judges to heel and presided over continuous attacks on NGOs, journalists and opposition politicians.

His misleadingly titled Serbian Progressive Party (SNS) dominated the television landscape, taking 58 percent of electoral programming time, compared to Saša Janković, the second-place candidate, who received just 7 percent. If you include coverage of Vučić’s activities as prime minister, he monopolized an astonishing 92 percent of the Serbian national TV programming devoted to politics.

Vučić has not only marched Serbia’s media into line; he has brought the country’s judges to heel and presided over continuous attacks on NGOs, journalists and opposition politicians. And he has used an over-hyped anti-corruption campaign to target the opposition while ignoring well-founded allegations against tycoons and his own party.

And yet, despite the heavily tilted playing field, the SNS has not managed to increase its support base, which has stagnated at under 2 million of the roughly 6.7 million Serbs registered to vote. They could well lose Belgrade's local elections next May; failure there spelled the beginning of the end for our last despot, Slobodan Milošević.

Stirrings of discontent can already be heard in the capital’s Savamala district, where anti-corruption demonstrators are protesting an opaque deal with an Abu Dhabi investor to develop Belgrade’s vibrant waterfront. Authorities awarded the project without public consultation.

Last spring, masked men showed up late one night and tied up scores of onlookers in the area to make way for construction workers, who demolished private property unannounced. When the police were called, they refused to help. The men in balaclavas were alleged to be acting on the orders of the city mayor — one of Vučić's close collaborators.

For me, the protests evoke memories of October 2000, when I stood with six friends to take part in the popular revolution that overthrew Milošević. Three of those friends have since moved abroad rather than face a future under a corrupt oligarchy that dominates politics and the economy. Of the three that stayed, only one voted; the others saw the activity as a pointless exercise.

They’re far from the only ones. A million Serbs have voted with their feet, preferring to live outside the country rather than face a future inside an autocracy. Only 1 percent of Serbs living abroad voted. Inside Serbia, nearly half the country didn’t bother to vote at all. Of those who did, nearly 10 percent registered a protest vote with comedian Luka Maksimović (better known as Beli Preletačević).

Brussels should be paying close attention to the dissatisfied. On Monday night, after the election results became clear, thousands of students organized spontaneously on social networks and took to the streets of Belgrade to protest the government. These are the people who cherish freedom, transparency and the rule of law; who still want EU membership and oppose the autocracy being ushered in by Vučić.

By endorsing Vučić's brand of politics (pro-European market, anti-European principles) EU leaders risk alienating the bloc’s Serbian supporters — eating away at the remaining 43 percent who want to join and bolstering those who don't.

Instead, the bloc should be putting pressure on Vučić to loosen his grip on the judiciary, the media and civil society and to allow meaningful investigations into opaque contracts like the Belgrade waterfront deal. If support for the EU in Serbia continues to plunge, Brussels will have no one to blame but itself.

Srđan Cvijić is a senior policy analyst at the Open Society European Policy Institute.