Spain Votes in Wide-Open Election after Tense Campaign

After a tense campaign dominated by issues such as national identity and gender equality, the likelihood that any coalition deal will take weeks or months to be brokered will feed into a broader mood of political uncertainty across Europe.

At least five parties from across the political spectrum have a chance of being in government and they could struggle to agree on a deal between them, meaning a repeat election is one of several possible outcomes.

A few things are clear, however, based on opinion polls and conversations with party insiders. No single party will get a majority; the Socialist party of outgoing Prime Minister Pedro Sanchez is leading the race; and there will be lawmakers from the far-right Vox party.

Beyond that, the result is too close to call.

Voting started at 9 am (0700 GMT) and ends at 8 pm in mainland Spain for what will be the country's third national election in four years, each of which has brought a further dislocation of the political landscape.

"After many years of instability and uncertainty, it's important that today we send a clear, defined message about the Spain we want. And from there a broad parliamentary majority must be built that can support a stable government," Sanchez told reporters after voting in a polling station near Madrid.

It is uncertain if Sanchez will manage to stay in office and how many allies he would need to gather together in order to do so.

If, in addition to far-left anti-austerity party Podemos and other small parties, Sanchez also needs the support of Catalan separatist lawmakers, talks will be long and their outcome unclear.

Opinion polls, which ended on Monday, have suggested it will be harder for a right wing split between three parties - the center-right Ciudadanos, conservative People's Party (PP) and Vox - to clinch a majority, but this scenario is within polls' margin of error and cannot be ruled out.

Voting in Barcelona, Ciudadanos leader Albert Rivera renewed calls to oust Sanchez, whose more conciliatory tone toward Catalan separatists has angered the right, which called Sanchez a "traitor" throughout a campaign often dominated by the secession crisis.

"These are not any normal elections. At stake is whether we want to remain united, if we want to continue being free and equal citizens, if we want a Spain that looks to the past or the future, a country of extremes or of moderation," Rivera told reporters after casting his ballot.

With the trauma of military dictatorship under Francisco Franco, who died in 1975, still fresh in the memory for its older generation, Spain had long been seen as resistant to the wave of nationalist, populist parties spreading across much of Europe.

Some voters still stood by this. "I'm more of a Ciudadanos or PP voter but I'm so scared of Vox that I voted for the left-wing bloc, for the Socialists," Julio Cesar Galdon, a 27-year-old political science graduate said after voting in central Madrid, Reuters reported.

But this time Vox will get seats, boosted by voter discontent with traditional parties, its focus on widespread anger at Catalonia's independence drive, and non-mainstream views that include opposing a law on gender violence it says discriminates against men.

One of several unknowns is how big an entry Vox will make in parliament's lower house, with opinion polls having given a wide range of forecasts and struggled to pin down the party's voter base.

"I voted Vox," said Pedro, a 57-year-old civil servant who used to vote center-right but changed his mind this time.

"This campaign has been different. There are two sides, one fighting more for the interests of Spaniards and another fighting for its own interest," he said while voting in Madrid, adding that he preferred not to give his full name.

The high number of undecided voters - in some surveys as many as four in ten - has also complicated the task of predicting the outcome, as have the intricacies of a complex electoral system under which 52 constituencies elect 350 lawmakers.

That system is untested in Spain's new political era, marked by the definitive end of the long-held dominance of the PP and the Socialists.

Voters in the depopulating rural heartlands - many of whom are old and may well feel little direct connection to the country's young, male, urban political elite - are of particular importance.

They proportionally elect more lawmakers than the inhabitants of big cities, but at the same time the cut-off point for parliamentary representation there is trickier to reach, making the outcome harder to predict the more parties there are.

Another unknown is the impact of two televised debates early in the week. They may well influence the outcome in a country where a small difference in votes can make a huge difference in terms of seats.

While Vox's leader was excluded from the TV debates, which analysts said could help his narrative of being against "the system", Sanchez was rather subdued and Podemos leader Pablo Iglesias, whose party was struggling in polls, was considered by many as having given a strong performance.

"I believe we achieved something important for everyone, regardless of their politics, by debating ideas and rejecting insult, tension and over-reaction," Iglesias said of his party's campaign after voting on Sunday morning.

An opinion poll will be published at 8 pm, and results will trickle in through the evening with almost all votes counted by midnight.

In the past two elections, the 8 pm opinion polls failed to give an accurate picture of the eventual outcome and it took time for preliminary results to do so.