Why Spain's Election Is Almost Impossible to Predict

On December 20, Spain will hold what looks to be the most open election in its modern history. Latest polls show that neither the conservative People's Party (PP) , which is currently in power , nor its historic rival, the center-left Socialist Workers' Party (PSOE), will win a majority. The two emergent parties—the far-left Podemos and right-wing Ciudadanos—are also unlikely to win outright, having muscled their way into contention over the last two years.

A poll conducted by Spanish survey company Metroscopia and published in national daily El País in the last week of November showed PP, PSOE and Ciudadanos tied at 22 percent of the vote, with Podemos earning 17 percent. Earlier this week, another poll in El Pais had PP winning 109 seats, PSOE winning 90, Podemos and its regional affiliates winning 60, and Ciudadanos winning 60.

The objective for any one party is to win a 176-seat majority at the 350-seat parliament, a feat that is looking increasingly unlikely. And two of the parties have already ruled out most of the potential coalition combinations.

"This is a completely unprecedented fragmentation of the political party system in Spain," says Antonio Barroso, eurozone analyst at corporate advisory firm Teneo Intelligence. "The two new parties, Ciudadanos and Podemos have campaigned on an anti-corruption platform and they know that they will be punished by voters in the next election if they jump into bed with either the PP or PSOE."

On Friday, PP leader and incumbent Prime Minister Mariano Rajoy ruled out a possible coalition between his party and the PSOE, rejecting the kind of partnership that in Germany has the Social Democratic Party propping up Angela Merkel's Christian Democrats .

Previously, Albert Rivera, leader of Ciudadanos, had also rebuffed ideas of joining an alliance with either the PP or the PSOE. While Rajoy has warned of the possible formation of a PSOE and Podemos coalition, the two parties found it difficult to strike a deal during May's municipal elections and may not find it easier this time round.

As Spain prepares to go to the polls on Sunday, the country's main parties are suffering the effects of a renewed war on corruption. Spanish judges began 2015 with a backlog of corruption cases involving a total of 2,000 people. Several of the defendants are members of the PP, the PSOE and the Royal Family alleged to be involved in various scandals like the infamous Gürtel case, which implicates the PP in bribery, tax evasion and money laundering.

In the meantime Podemos, made up of left-wing professors and activists as opposed to career politicians, has repeatedly topped polls as the country's most popular party. And over the summer, Ciudadanos leader and Catalan lawyer Rivera became Spain's most popular politician when he vowed to "clean" the system of corruption. Sunday's election is the first general election for both parties, and poll results indicate they are entering the race with blank slates for their reputations. But still, PSOE leader Pedro Sánchez was voted the second most popular politician, way ahead of Podemos' Pablo Iglesias Turrión and Prime Minister Rajoy.

"Forming a strong government will be difficult," Barroso says. "The incentives for a coalition are very low."

Minority governments have existed in Spain in the past, but Barroso says those situations were different in that one national party usually emerged as a clear victor and then looked to make deals with regional "nationalist" parties, such as those representing Catalonia and the Basque region.

Barroso notes that in 1996, José María Aznar's PP won 156 seats and passed a budget by getting support from nationalist parties. "Now if PP wins it will fall way below that figure," he says. "No party is likely to come close to that as the vote is now split in four directions. And even if they did come close, nationalist parties have turned more confrontational with Madrid since 1996."

Indeed, in Catalonia acting regional president Artur Mas has warned citizens against voting for either the PP or Ciudadanos as he considers a coalition between the two to "go against Catalonia," RTVE reports. His pro-independence alliance has been amplifying the separatist sentiment in the region since it held a controversial, non-binding independence referendum in November. He now stands closer than ever to a free Catalonia as a deal between his party and the far-left CUP in the Catalan parliament will give the region its first entirely pro-independence local government.

Along with corruption and Catalonia, voters also have the economy on their minds, according to Barroso. "Those are the issues that the four biggest parties have been campaigning on," he says. "Spain has been the eurozone's success story for market recovery but stability has not brought in reforms to change Spain into a knowledge-intensive economy. Unemployment remains high."

The Podemos platform has been clearly anti-austerity, while the PP has been showing its opposition to the idea by celebrating their record of handling the economy responsibly. Rajoy's government recently enjoyed a drop in unemployment figures of over 27,000—but that only brought the jobless rate back down to the same figure (22 percent) it was at before Rajoy's government came to power in 2011.

"Whatever government is formed out of these elections, [they] will have to negotiate a deal that can continue reducing the fiscal deficit and implement reforms," Barroso says. "Political instability will really matter if there is some sort of shock to the system, like the financial crisis."

All of these issues ride on what happens on election day. But according to Barroso, there is one day more important to Spain's future than December 20. "December the 21st," he says. "That is when all the discussions will begin and we may see something that we have never seen before in Spain."