(Bloomberg) -- Spaniards go to the polls on Sunday to pick thousands of city and regional representatives in a vote seen as the bellwether of a general election in December that will pit Socialist Prime Minister Pedro Sanchez against right-wing People’s Party leader Alberto Nunez Feijoo.

Sanchez is looking to hold onto key battlegrounds such as the region of Valencia and regain control of electoral bastion Barcelona, which was lost during Europe’s debt crisis and would vindicate his strategy of rapprochement with Catalan separatists.

Recent polls show Feijoo’s Populars are close to flipping some regions, however, as well as tightening their grip on Spain’s richest area, which includes the capital Madrid.

“If Sanchez isn’t able to reclaim Barcelona and loses Valencia, his government will likely start a process of decay as the prospects of winning the general vote sour,” said Manuel Mostaza, head of public affairs at Madrid-based consultancy Atrevia.

A more resilient-than-expected economy could help Sanchez. He fanfares falling unemployment as a key achievement of his administration, which has shelled out billions to protect businesses during the Covid pandemic and war in Ukraine. The pace of inflation in the euro zone’s fourth-largest economy is about half that of the currency bloc overall, and food cost rises also slowed sharply last month, although they remain stubbornly high.

Sanchez has introduced a range of measures including discounts on train fares for the young, cheap cinema tickets for the elderly, and investment in mental health, as he tries to brandish his Socialist credentials. He has also placed access to housing at the center of his campaign, having introduced loan guarantees for young people trying to buy homes.

Key wins on Sunday would boost the 51-year-old’s chances of reelection to pursue pro-European Union policies that have made him a key voice of the liberal left on the continent.

Feijoo has accused the prime minister of opportunism, meanwhile, and has attacked him over a spreading vote-buying scandal involving some candidates from his party and allies. Police detained at least nine people in the Spanish enclave of Melilla, in North Africa, earlier this month for alleged election fraud, as well as two Socialist candidates over similar allegations in a town in southeastern Spain.

The 61-year-old lawyer, who ruled the northwestern region of Galicia for 15 years, is trying to strike a moderate tone to attract centrist voters to his camp.

Both Sanchez and Feijoo will need the support of minority allies on Sunday. The Populars may be forced to form alliances with far-right party Vox to rule in regions where it doesn’t win an absolute majority. The Socialists will likely seek to replicate the central government’s alliance with radical left groups and other regional parties to maintain control of some cities and areas.

Sanchez’s minority coalition partner, Unidas Podemos, is expected to lose support in the vote as its nationwide appeal wanes. The decline of the far-left alliance, which emerged as a protest movement after the last financial crisis, could push it to join the Sumar platform of Labor Minister Yolanda Diaz, who is trying to bring together the far-left vote under her candidacy for the premiership.

--With assistance from Ainhoa Goyeneche.

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