AMID sweltering heat, Spanish voters head to the polls today to elect a new government.

As parts of the country have faced temperatures of over 40 Celsius (104 Fahrenheit), there is a real sense that anything could happen.

“It’s kind of an atomic bomb in terms of participation,” was how Aitor ­Hernandez-Morales, a reporter for the ­online ­newspaper Politico, summed up the mood, echoing the views of many ­election watchers.

“We just have no idea what’s going to happen. There’s a massive heat wave. A third of the country is on vacation. ­Seven per cent of the population is voting by mail. Even the political scientists I’m speaking to admit they’re not sure which way things will go,” Hernandez-Morales added.

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Right up until today’s ballot, there has been debate and speculation as to how this vote – the latest ever in Spain’s ­summer – would play out. An estimated record 2.6 million people requested postal ballots and many voters have been ­rushing to pick up and send back their votes from their holidays on the beach with at least 10 million of Spain’s 37 million electors on holiday.

Their absence is already being felt at polling stations – which are typically staffed by registered voters, who are ­conscripted via a lottery system – as well as in Spain’s post offices, some of which have already recorded “bottleneck and queues” as more and more voters opt to vote by mail.

Will the summer vote give advantage to the left, or right? This is only one of many questions surrounding today’s ballot.

Research shows that generally in Spain, conservative turnout is consistently strong and it is the number of left voters that ebbs and flows.

Unpredictable as things are, if the final opinion polls allowed under Spanish law before today’s ballot are anything to go by, then the conservative People’s Party (PP) led by Alberto Nunez Feijoo ­appear ahead of incumbent prime minister (below) ­Pedro Sanchez’s ruling Socialists (PSOE) who lead the coalition government.

The National:

But even with such an advantage in the polls, the PP at the very least would need the support of far-right party Vox to ­govern, a scenario that would leave its leader, Santiago Abascal, as a potential kingmaker in the wake of the election.

That, in turn, could herald weeks of ­volatile coalition negotiations. It would also mark the first time a far-right party holds a share of power in Spain since the end of the Franco dictatorship in 1975.

Such is Vox’s political complexion that one commentator recently dubbed it a “Francoist tribute act”, while another said its manifesto is virtually a ­“copy-and-paste of the tenets of the Franco regime”.

Among its policies, it wants to repeal a law cementing LGBT+ rights. Vox also ­rejects worries about rising temperatures – despite the current record heatwave – as “climate fanaticism”.

It is also a party that uses language like “Muslim invasion” in its ­anti-immigration campaigns and wants to erect walls round Spain’s north African enclaves of Ceuta and Melilla to deter migrants.

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Vox too opposes abortion and it has an election manifesto that calls for the ­repeal of laws on violence against ­women. In an echo of the Francoist days, Vox also wants to maintain what it sees as the ­“territorial integrity” of Spain, banning pro-independence parties from Catalonia to the Basque Country and Galicia.

But despite such contentious ­policies, ever since the electoral thrashing Sanchez’s coalition took in May’s local polls, Vox is now in power in more than 140 municipalities – either alone or in conjunction with the PP – and also jointly governs with the PP in two other regions.

As for today’s election, according to the main Spanish pollsters, which are barred from publishing surveys after last ­Tuesday, the PP would garner 131 to 151 seats in the 350-member lower house, ­falling short of an outright majority of 176.

Spain’s El Pais daily newspaper – using a probabilistic electoral model it has been publishing since 2016 and based on polls and simulations – published an estimate of seats based on the average of polls.

It suggested that the PP would have around 142 seats, followed by the PSOE with 108, and far-right Vox with 35 and the left-wing Sumar with 34. The rest of the political forces would have around 31 seats in total.

Turnout then will be crucial today and in recent years it has ranged between 58% to 75% but all parties will need to put in extra effort to get voters out and away from the beach.

Certainly, when seen from Sanchez’s perspective, the result of today’s ­election will depend on the extent to which his PSOE can mobilise its voters. The prime minister has placed great emphasis on the areas where his government has ­performed well, notably on the economy and social policy.

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After a faltering performance during and immediately after the pandemic, Spain’s economy is now doing better in terms of growth, inflation and job ­creation than the average European one. That message however did not avert a ­convincing defeat for Sanchez and his PSOE in local and regional elections in May.

Since then, the Socialist leader has been trying to reassure and ­re-energise ­progressive voters framing today’s ­election by drawing parallels between Spain and other countries where ­voting has taken place in the shadow of an ­illiberal regime from the right.

Above all else it has been the role played and relationships created ­between ­political allies and bedfellows in this ­election that has been the focus ­throughout the campaign for all sides.

To that end, Sanchez has been warning that a PP-Vox coalition government would find Spain being dragged backwards into “a tunnel that leads us to we don’t know where”.

He has stressed too that today’s ­election, “will clarify if Spaniards want a government on the side of Joe Biden or Donald Trump, of Lula da Silva or Jair ­Bolsonaro”.

Speaking to The New York Times a few days ago, Pablo Simon, a political scientist at Madrid’s Carlos III University, described the ballot as “an election about partners… the partners of the right and the partners of the left”.

If Sanchez is quick to flag up the ­dangers of a partnership between the PP and Vox then in turn they use the prime minister’s allies to depict a political positioning they call “Sanchismo”, which they define as his willingness to make any alliance to stay in power.

In his opponents’ telling, Sanchez lost all credibility by his alliance with Spain’s pro-independence parties, in particular the Catalans. He stands accused, ­according to his PP and Vox opponents, of a “betrayal” of Spain after making a series of concessions in which nine Catalan leaders were pardoned for their role in the region’s independence bid and for reforming sedition laws under which they were charged.

According to Professor Omar G ­Encarnacion, author of Democracy ­Without Justice In Spain: The Politics of Forgetting, all of the nation’s political forces have exploited the independence parties for political gain.

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“In recent years the right, including the PP, has won elections by railing against the separatists, even at the ­expense of ­collapsing in Catalonia and the Basque Country, home to Spain’s leading ­separatist movements,” ­Encarnacion ­observed recently in an op-ed for The New York Times.

But others too beyond Spain’s ­contesting political parties are ­watching today’s election with considerable ­interest. Should Spain move to the right in the coming days it would mark only the latest, albeit most striking shift, of recent times. Already across Europe a pattern is developing whereby far-right parties once considered beyond the pale have entered into the continent’s mainstream and in many places now wield genuine power.

In Germany, for example, polls show that the Alternative for Germany (AfD) party has overtaken the governing Social Democratic Party (SPD) to become the second-most popular party in Germany.

In Austria, the pro-Vladimir Putin ­Freedom Party (FPO), which was once led by a former Nazi, is polling at 28% a year ahead of elections, higher than its centre-right and centre-left rivals.

Then in Greece, Spartans, a party ­established just weeks before recent elections and supported by leading lights of the now-defunct neo-Nazi Golden Dawn, unexpectedly won 4.7% of the vote.

Perhaps the most illustrative case in point is Italy, whose prime minister ­Giorgia Meloni – a long-time Vox ­supporter – backed the Spanish party which is a natural right-wing ally of its Italian counterpart Brothers of Italy.

Meloni told Vox hard-liners that their success in Sunday’s elections would ­usher in “a change in the politics of ­Europe” and that “the hour of the patriots has ­arrived”. Vox has also won public ­backing from Hungary’s Viktor Orban and ­Poland’s Mateusz Morawiecki.

With Spain currently holding the ­presidency of the Council of the ­European Union, should Vox make ­electoral ­advances in the coming days or have a role in Spain’s next government it would be ­potentially significant for Europe’s ­politics, giving the right a foothold in the EU’s fourth-largest economy.

Vox leader Santiago Abascal was ­pulling no punches at an election rally last week when he declared that Spain’s domestic policy was “decided either by the bureaucrats in Brussels or the Basque and Catalan separatists”.

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Disquieting as such remarks are for many European politicians, observers are predicting that the EU will move further to the right after the European Parliament elections next year and Spain’s election today will help determine whether it will be part of that shift.

Five years ago in an interview with The Washington Post, Spain’s then foreign minister Josep Borrell was at pains to ­explain why his country had so far resisted the siren song of right-wing populism.

“We have been vaccinated by the [Spanish] civil war and by the long years of [Francisco] Franco’s dictatorship,” he told the Post at the time.

Spain’s experience of anti-democratic, fascist rule has inoculated it from the “virus” of the illiberalism seen in some of its European neighbours, Borrell told the paper’s foreign affairs columnist Ishaan Tharoor.

Whether Spain remains “inoculated” only the results of today’s election will tell.

With political expediency everywhere on display in this election and the ­demise of centrist parties seen in ­previous ­elections, analysts say the starker ­ideological choices have left some ­Spanish voters in a mood to block what they don’t like, rather than pick what they do.

A straw poll of two dozen voters ­conducted around the country by ­Reuters news agency found many with little ­enthusiasm for any party and torn ­between what they viewed as the least bad choice. This sense was reinforced by opinion surveys reporting that around 12.5% of people who plan to vote were still undecided at the start of last week.

Polls open at 9am (0800 BST) today and close at 8pm (1900 BST), when exit polls will be released. A near-definitive total of seats only becomes clear by ­midnight (23:00 BST) and the final result is ­expected to be decided by fewer than a million votes, fewer than 10 seats in a 350-seat parliament, experts say.

As it stands, no party appears able to secure an outright majority and in a ­fragmented parliament three scenarios are currently the most likely.

The first is that reflected by most polls, in which the PP takes the most seats of any party but needing Vox to get anywhere near an overall majority.

The second is that Sanchez’s socialist minority government could continue with external support from the Catalan and Basque nationalists.

And the third possibility is that the ­parliamentary parties are so evenly ­divided that repeat elections are ­needed which would necessitate Sanchez’s ­Socialists continuing as a caretaker ­government at least until the next vote.

With such an unpredictable election the only certainty is that today will be a hot one in Spain – in every sense of the word.