Spain’s current Prime Minister Pedro Sánchez and his Spanish Workers’ Socialist Party (PSOE) have won the most seats in Spain’s general election — but their victory falls short of a majority needed to take outright control of the government.

Sánchez and his center-left PSOE are on pace to claim 122 seats, with more than 90 percent of the vote counted. It’s a gain from the 84 seats the party currently holds, but not exactly close to the 176 needed for a majority. Now Sánchez and his party will have to try to form a government with the support of other parties

PSOE will likely enter into an alliance with the left-wing Unidas-Podemos, which secured 42 seats. That still leaves PSOE and Unidas-Podemos shy of a majority, which means they may have to rely on smaller, regional parties to form a government. It may be an extremely difficult task amid Spain’s fragmented political landscape.

ÚLTIMA HORA https://t.co/yhrcWg4dPj El PSOE pierde un escaño, hasta los 122, con más del 90% escrutado. Con Podemos suma 164 diputados pic.twitter.com/Qe8R591cif — EL PAÍS (@el_pais) April 28, 2019

PSOE’s victory is somewhat tempered by the success of Vox, a surging right-wing, anti-immigrant political party that’s projected to take 24 seats in Spain’s Congress. Vox’s performance fell short of some early forecasts, but this breakthrough is still significant. Vox was a political afterthought less than three years ago. Now, a far-right party has won spots in Spain’s legislature for the first time since the country transitioned to democracy 40 years ago.

In those 40 years, two political parties dominated Spanish politics: the conservative Partido Popular (PP) and the center-left PSOE. But, in recent elections, smaller parties have chipped away at their influence. That trend continued in 2019.

PSOE’s mixed success on Sunday is a symptom of Spain’s political polarization

Spain’s election outcome will do little to settle the political problems the country faces, including the question of Catalonia, which is still paralyzing the country’s politics more than a year after the illegal 2017 Catalonian independence referendum.

And now Sánchez and PSOE will need to rely on Unidas-Podemos and smaller, regional parties to govern.

This is a potentially volatile arrangement. Catalan and Basque country parties supported the PSOE in its successful bid to oust the former prime minister and then-PP leader, Mariano Rajoy, in June 2018, allowing Sánchez to become prime minister.

But, in February, Catalan nationalists doomed Sánchez’s leadership, when they joined with the opposition to defeat Sánchez’s budget in Congress, forcing him to call these snap elections in April.

The PSOE might be able to govern without support from Catalan nationalists, as there appear to be a few combinations that would yield a 176-majority. But, it won’t be clear until all the votes are tallied, and Sánchez begins to build his coalition.

Spain’s politics are proving to be as volatile as ever after this election. Smaller parties are continuing to erode the traditional dominance of the PSOE and PP. Vox’s national gains, though short of expectations, prove that a far-right movement has officially arrived in Spain.

PSOE succeeded at the polls on Sunday. But now comes the extremely difficult task of forming a government — and Spain’s political divisions could still derail that, too.