On the list of longest-ruling heads of state, Milo Djukanovic has few competitors. Not counting two brief absences that Djukanovic himself initiated, only the likes of Robert Mugabe of Zimbabwe, Ali Khamenei of Iran and Hun Sen of Cambodia outpace him. For the last quarter century, Djukanovic has been at the forefront of politics in Montenegro, one of the smallest countries in the Balkans. He has switched between prime minister and president, and his political ideology has shifted with the times: at first communist, then nationalist and, 10 years ago, an ideologue who pushed to secede from Serbia. Today, he's a leading voice for EU and NATO integration.

Controversy without consequence

It is therefore unsurprising that Sunday's parliamentary election is less about party programs and a vision for the country than it is about whether Milo – as the prime minister is commonly referred to – should stay or go.

"The political scene is split: Those who want to support Djukanovic and his governing model, and those who want to see an end to his reign," said Marko Vesovic, a journalist for Dan, a daily newspaper critical of the current government. "This is the choice Montenegrins have had for decades already." He defines the "Djukanovic Model" as a neoliberal sellout of state assets and close relations with organized crime.

Such claims have long been commonplace in Montenegro, yet they bounce right off the long-time head of state. A 2003 criminal investigation by Italian authorities into his alleged involvement in cigarette smuggling in the 1990s was eventually dropped. A nepotism scandal caught on tape three years ago, which involved high-level members of Milo's Democratic Party of Socialists, also had little negative affect. The British newspaper, The Independent, has described Djukanovic as one of the world's richest politicians, though how he has come into wealth remains a "mystery."

Protests in 2015 attracted thousands of people

The air of cronyism and corruption are reason enough to vote against Djukanovic, as far as the opposition is concerned. However, his repeated political victories have been so one-sided, he has occasionally mocked the opposition for their quarter-century-long failure to unseat him.

This time, things could be different: Voters have had enough, Vesovic said. "It's quite possible for the opposition parties to win enough votes to form a broad governing majority," he said.

Hopelessly divided

The country of just 620,000 people will be voting for no fewer than 17 lists including a total of 34 parties on Sunday. Opposition parties, therefore, face the danger of splitting the vote against Djukanovic to such an extent that many won't exceed the three percent hurdle required for parliamentary representation. The parties have been locked in a long-standing struggle over which one is the "true alternative."

The Democratic Front - a coalition of convenience between a pro-western and pro-Serbian party - could come out on top of the opposition with 15 percent of the vote, despite the lack of credible polling data. However, the group has an internal struggle over NATO membership, as does the entire country: One poll has 46 percent in favor joining the western military alliance and 39 percent vehemently opposed to it; other polls put the anti-NATO movement out front.

NATO decided in May to allow Montenegro's membership, which now has to be ratified by member states' parliaments. Closer EU relations are hindered by ongoing complaints from Brussels about the justice system and press freedom in the Balkan state.

For Djukanovic, entering NATO would be a triumph. His campaign posters call membership a "breakthrough for civilization" and his government sees it as a definitive out from the "Serbian and Russian zone of influence."

The country is split over NATO membership.

Clean election?

Preventing election fraud is more important than any campaign theme, said Boris Raonic, program director of an NGO overseeing the election. "This is the first election to be heavily monitored," he said. A rumor is going around Montenegro suggesting an invisible activist network supportive of the governing party is buying up national identity cards to suppress the vote. Civil servants have spoken of pressure to vote "correctly."

"There is no evidence of these machinations," Raonic said. "Neither from the opposition - although they have ministers in the transitional government and dozens of officials at the local level - nor from non-governmental organizations." He views this as the first legitimate election since the end of communism.