Socialists set to reign in Spain, but not without support

Spain's Prime Minister and Socialist Party leader Pedro Sanchez gestures to supporters outside the party headquarters following the general election in Madrid, Spain, Sunday, April 28, 2019. (AP Photo/Bernat Armangue)

Spanish Prime Minister and Socialist Party candidate Pedro Sanchez gestures to supporters gathered at the party headquarters waiting for results of the general election in Madrid, Sunday, April 28, 2019. Spain's governing Socialists won the country's national election Sunday but will need the backing of smaller parties to stay in power, while a far-right party rode a groundswell of support to enter the lower house of parliament for the first time in four decades, provisional results showed. (AP Photo/Andrea Comas)

Spain's third parliamentary election in less than four years has done little to dispel uncertainty over the political future of the eurozone's fourth largest economy.

The center-left Socialist party won re-election in Sunday's ballot, collecting nearly 29% of votes, and will try to form a government. It would be one of only a handful of socialist governments in the European Union.

But with only 123 seats in the 350-seat Congress of Deputies, Spain's parliament, it needs to negotiate the support of smaller rival parties to pass legislation.

Even an alliance with the far-left, anti-austerity party United We Can wouldn't give the Socialists the key number of 176 seats.

Spain's political landscape has fragmented further, with far-right party Vox claiming its first seats in the national parliament.