In what would be the first parliamentary representation for the far-right in decades, a survey found the Vox party could win 8-10 seats and subsequently take control over the region of Andalusia, south of the country. Official results are expected at 10.15 local time (9.15 GMT). If it is confirmed that Vox won seats, it would be the first sign of the nationalist surge that has swept other European countries reaching Spain, long seen as immune because many still remember the military dictatorship that ended in 1975. Andalusia has some of the highest unemployment rates in Europe and is the main arrival point in Spain for migrants crossing the Mediterranean.
The number reaching Spain has surged in the past year as traffic on the main sea route to Europe, from Libya to Italy, has slowed.
The GAD3 poll, carried out for the newspaper ABC between November 19 to 30, had the Socialists who hold power in Madrid getting most votes, but losing ground compared to the last election in what has been dubbed the very first electoral test for Prime Minister Pedro Sanchez.
Socialist Mr Sanchez’s minority government has been unable to pass a budget in Madrid since taking office last summer.
The election in Spain’s most populous region took place in a political landscape in which major parties find it harder and harder to secure majorities.
There are 109 seats in Andalusia’s regional parliament.
Should Vox win, they will take power of the south coast region and follow in the footsteps of other right-wing parties who have done the same across Europe such as Italy’s League and Hungary’s Fidesz to name a few.
Mr Sanchez hit headlines in the UK and across Europe for refusing the vote in favour for Prime Minister Theresa May’s Brexit deal, which will tie the UK to the EU’s customs union and single market.
He demanded the region of Gibraltar – British territory that Spain has long desired – be taken off the table during negations so he can have a say on its future relationship with the bloc.
Mrs May caved into his demand, much to the dismay of Brexiteers, and Mr Sanchez voted in favour of the deal less than 24 horas later.