(Bloomberg) -- Spaniards go to the polls on Sunday for the second time this year as the country strives to break a political logjam that’s threatening economic momentum and allowing disputes over national unity to fester.

Polling booths open at 9 a.m. and close at 8 p.m. with voters choosing 350 deputies and 208 senators.

It’s a procedure Spanish voters are now well-accustomed to -- this election is the fourth since 2015 -- but the campaign is different from the last contest in April. Political opinion has been further splintered in recent weeks by the exhumation of the late dictator Francisco Franco and a court decision to sentence the former leaders of the Catalan independence movement to lengthy jail terms.

Even so, the result may be similar: a deadlock in which neither alliances of forces on the left and right have a clear path to form a government. Unless the warring factions can find a compromise, they may face a backlash from an angry electorate unwilling to sanction yet another election.

Surveys taken before a polling blackout began on Nov. 5 showed the Socialists of acting Prime Minister Pedro Sanchez in the lead, but struggling to maintain the momentum they had in April.

The main opposition, the People’s Party, looked set to stage a partial recovery from its previous poor result, while Ciudadanos is set to hemorrhage support. It was a centrist party before it started to zig-zag across the political map in search of votes.

If Sanchez is to form a government, he may have to repair relations with Pablo Iglesias, the leader of Podemos, an anti-austerity party that shares many of the Socialists’ social goals. Attempts to forge an alliance over the summer ended in recriminations over differences on how to handle Catalan separatism.

Vox, a Spanish nationalist party, looks poised for a strong showing. That’s partly due to a backlash among conservative Spanish voters to the rioting in Catalan cities since jail terms totaling 100 years were handed down to nine separatist leaders for their part in staging a bid to split from Spain in 2017.

Sanchez’s decision last month to go ahead with the exhumation of Franco from his tomb in a mountain basilica outside Madrid has also mobilized Vox’s support. By sharpening antipathies over the ideological divide of the Spanish Civil War, Sanchez is trying to energize his own base of supporters.

These dramas have played out against the broader canvass of a slowing economy.

On Tuesday, Spain’s statistics agency published data showing the ranks of the registered unemployed had swelled by nearly 100,000 in October, a 3.2% increase that was the biggest monthly percentage jump since January 2012 when the country was in full financial crisis.

While Spanish growth is still strong compared with other European Union peers, the economy became an election issue in the last days of the campaign.

To contact the reporter on this story: Charles Penty in Madrid at cpenty@bloomberg.net

To contact the editors responsible for this story: Chad Thomas at cthomas16@bloomberg.net, Caroline Alexander, Flavia Krause-Jackson

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