Almost everyone in Spain expected the Spanish right to win Sunday’s general election. All the polls said so, all the political pundits said so too.

The only unknown was whether or not the centre-right Partido Popular (PP) would go into coalition with far-right party Vox, or win a big enough landslide to get an overall majority and govern alone.

But when the results came in, neither the PP nor Prime Minister Pedro Sánchez’s ruling PSOE had a majority big enough to govern. The PP won the most votes but underwhelmed, performing poorly compared to pollster’s predictions, and its potential coalition partner Vox lost 19 seats, denying the Spanish right of the majority everyone had expected.

READ ALSO: Five key takeaways from Spain’s general election

Of the left and right blocks in Spanish politics, it now seems more likely that Sánchez’s PSOE is more likely to find a coalition majority and govern again. But how is it possible that the PP won the most votes and seats but didn’t win the election? For many foreigners in Spain, this may seem like a strange, even undemocratic outcome.

The answer lies in Spain’s electoral system and power-wielding smaller regional parties.

How does the system work?

First things first, understand the system: in general elections, Spaniards elect representatives to Spain’s national legislature, the Cortes Generales, which is like its Congress or Parliament. The body is made up of two chambers: the Senate, and the Congress of Deputies, which is made up of 350 representatives. 

Spain’s fifty provinces each has a constituency that elects (at least) two seats. The autonomous cities of Ceuta and Melilla elect one member each.

The remaining 248 seats are spread out among the fifty provinces, but rather than allocating them evenly across the board, there are decided according to population. 

An absolute majority in the Spanish Congress means obtaining more than half of the seats plus one in the House of Deputies: half is 175, so therefore the absolute majority is 176 seats. Remember that number because it’s important to understanding how the PP can win the most votes but not win the election overall.

What do the results mean?

As it has a tendency to do, Spanish politics threw up some surprises and defied the polls on Sunday night.

The PP won 136 seats in Spain’s Congress (33 percent of the vote), making it the party with both the most votes and seats. That means it should win the election, right? Not quite.

Though it was the most voted party, the 136 seats was far lower than pollsters had predicted, with most polls putting it in the 150-160 range. 

READ ALSO: Spain’s election gridlock: What happens next?

Crucially, potential coalition partner Vox also underperformed, losing 19 seats (down to 33 seats on 12.4 percent) and underperforming compared to polling.

Sánchez’s PSOE were forecast to lose seats, but actually managed to make small gains, winning 122 (and 31.7 percent of the vote) and left-wing electoral platform, Sumar, led by Labour Minister Yolanda Díaz, pretty much matched Vox with 31 seats (12.3 percent).

So who has a majority?

In short, nobody right now. And in the Spanish system, it’s not about who gets the most seats or votes, but who can get a majority. 

Now, remember that magic number: 176? The minimum number of seats in the Congress of Deputies necessary to get an absolute majority and therefore govern.

If we look at the congressional numbers, the PP and Vox’s underwhelming performance at the polls on Sunday mean they fall short of an absolute majority and will be forced to look for smaller coalition partners to back it up, something generally more difficult to do for right-wing parties.

If the PP has 136 seats, and Vox 33: 136 + 33 = 169 seats. That leaves the right block seven seats short of a majority, and picking up the support of smaller parties, likely some or all of PNV (Partido Nacionalista Vasco), UPN (Unión del Pueblo Navarro) and Coalición Canaria (CC), might not even get them across the line.

In reality, however, the incendiary rhetoric of the Spanish right on the campaign, particularly by Vox, towards regional parties makes any alliance unlikely.

So why can the left get in?

But how can it be possible the parties that came 2nd and 4th in vote share (PSOE and Sumar respectively) could form a government?

Coalition building for Sánchez’s PSOE is a little easier, namely because it has governed in coalition for the last five years and regional and separatist groups are more likely to lend their votes to the left than the right. 

READ ALSO: After inconclusive vote, Spain begins talks to avoid new election

If PSOE takes on Sumar deputies and gets the support of its parliamentary partners of the last five years – regional groups ERC, EH Bildu, and the PNV, combined with the abstention of Catalan party Junts – PSOE could get to 176 seats and Sánchez could, in theory, become Prime Minister again. 

There are a lot of moving parts, but if either block were to manage a workable coalition, it would probably be the Spanish left, which explains why the PP can the most votes and seats but still theoretically lose the election.

Is that fair?

In Spanish elections, the ‘D’Hondt law’ is used, a proportional calculation system created at the end of the 19th century by the Belgian jurist Victor D’Hondt.

The system, though more proportional than majoritarian systems primarily used in the English speaking world, notably the UK and USA, is not entirely proportional to the votes cast, and tends to reward the candidates or parties with the most votes and punishes those with the least.

This system tends to benefit the bigger parties and punish the smaller ones, and as result many do not consider the D’Hondt system to be a truly proportional system, but a system that is more likely to reward the bigger, more established parties. In Spain, one of the the PP or PSOE have always governed since Spain’s transition to democracy. The 2019-2023 PSOE-Podemos coalition, propped up by regional groups, was somewhat unique. Following Sunday’s results, however, it seems that there will be another one.

Of course, both the PP and PSOE are largely in support the current system, namely because it favours them. However, it is not in their interests to reform the system as it preserves their power.

But in the divided and polarised world of Spanish politics in 2023, if coalition negations fail and neither block can gain a governable majority, there could well be another general election at the end of the year.