MADRID (AFP) -- Spain voted Sunday in its fourth general election in as many years amid heightened tensions over the separatist push in Catalonia that has fuelled a surge in support for upstart far-right party Vox.
The repeat polls were called after Prime Minister Pedro Sanchez failed to secure support from other parties following an inconclusive election in April which saw his Socialist party win the most votes, but no working majority in parliament.
However opinion polls suggest this new election will fail to break the deadlock. Neither the left nor the right look likely to win a ruling majority in Spain's 350-seat parliament.
The Socialists are on track to finish top again, but with slightly fewer seats than the 123 they picked up in April, while the main opposition conservative Popular Party (PP) may strengthen its parliamentary presence.
But the most striking development could be the rise of the far-right Vox party, which could even jump to third-largest in parliament, according to polling.
After casting his ballot in Madrid, Sanchez urged Spaniards to head to the polls, saying "it is very important that we all participate to strengthen our democracy" and that the country "have the needed stability to be able to form a government".
The last election produced a near-record 76 percent turnout, which helped Sanchez who had mobilized left-leaning voters to oppose Vox but analysts warn the numbers will likely drop this time, as Spaniards suffer election fatigue.
The election comes as Spain finds itself increasingly polarized by the Catalan crisis, which has deepened in recent weeks.
Less than a month ago, the Supreme Court sentenced nine Catalan separatist leaders to lengthy jail terms over their role in a failed 2017 independence bid, sparking days of angry street protests in Barcelona and other Catalan cities that sometimes turned violent.
More than 600 people were injured in the protests, which saw demonstrators torching barricades and throwing stones and Molotov cocktails at police.
During a TV election debate PP leader Pablo Casado called for a "real government that will put order in Catalonia".
But the toughest line against the Catalan separatists has come from Vox leader Santiago Abascal.
He repeated his pledge to end the Catalan crisis by suspending Catalonia's regional autonomy, banning separatist parties and arresting its regional president, Quim Torra, who has vowed to continue the secession drive.