Mobilisation of voters, and the role of election monitors, played a big role in the opposition victory in both countries.

Last weekend, the DE civic action group in Hungary sent 70 election monitors to Serbia, to work with students’ movement representatives, visiting polling stations in the northern Serbian province of Vojvodina.

During the summer, even before the election was called, they held workshops to share their experience and methods from the Hungarian election with the Serbian students.

A key technique was to identify “infected” polling districts in advance – places where the surprisingly high number of votes for the governing party at previous elections suggested that voter intimidation or “chain voting” techniques were used.

“From around 16:00 on election day, we noticed groups of masked hooligans – Vučiċ supporters – gathering near voting stations,” Péter Klemm, a student activist from Subotica, told the BBC. “So we sent mobile teams, and started filming everything.”

Combined with the “stationary” monitors already in place, 20 to 30 volunteers at each threatened polling station acted as a strong deterrent, he believes, and prevented intimidation or fraud.

Orbán in Hungary, Vučiċ in Serbia, both looked invincible. Both were powerful leaders, in office for 16 and 14 years, who had taken over state institutions and established business empires overlapping the two countries.

Orban chose cheese, Vučiċ meat, when they sat down to a quick lunch of traditional burek pastries at a small, popular town centre bakery in Subotica almost a year ago.

They continued to a local winery, to talk about oil and other business deals – the planned Hungarian purchase of Serbia’s Nis oil refinery. The two nationalist leaders found much in common, in business and politics, not least their friendship with Vladimir Putin in Russia and Chinese President Xi Jinping, and their strong support for Milorad Dodik, the separatist leader of the Bosnian Serbs.

A high-speed railway between Belgrade and Budapest is being built with Chinese finance and know-how.