Vox could take 1.3 million votes from Spain's PSOE and 200,000 from the PP

Vox absorbs 1.3 million socialist votes and 200,000 from the PP

The shift in ballots suggested by the polls used in the electoral analysis points to a deeper movement: the PSOE would give up around 1.3 million votes while the PP would lose some 200,000, and much of that flow would swell Vox's ranks. The figure is far from a minor detail: it reshuffles the board, because the allocation of seats does not work as an arithmetic sum of voters' wills.

The D'Hondt system doesn't add, it divides

Here lies the crux of the matter. Two parties competing for the same space can win the same share of the vote and still end up with one fewer seat than the sum of their separate quotients. The mechanism is well known: Spain's electoral law calculates each party's quotients independently, province by province, and in small constituencies —with four to six seats— the last seat is decided by a handful of votes.

An example circulating in the analysis illustrates this starkly. In a five-seat province, with the PSOE at 38% and another left-wing force at 12%, a split of 35% for the PP and 15% for Vox gives the right three seats. If both parties split the vote evenly at 25%, the same 50% of votes translates into two seats. The lost seat goes to the PSOE without it gaining a single extra vote. The conclusion is uncomfortable for anyone who trusts simple arithmetic: the system rewards concentrated majorities and punishes fragmentation.

Where the game is played: small provinces

The map matters more than the total. In Navarre and the Basque Country the right's presence is virtually nil, and in Catalonia the PP arrives badly weakened while Vox contests its space, which benefits the PSC and the pro-independence parties. The key lies in the constituencies with few seats, where a shift in votes can make a seat disappear without the bloc as a whole losing real support.

Hence the reading that part of the analysis imposes: a Vox growing strongly can drag down the PP and, in doing so, reduce the right-wing bloc's total. The paradoxical result —more votes for the right, fewer seats— is exactly what the system is designed to produce when the contest takes place within the same space.

The calculation that keeps the PSOE standing

Some argue that the PSOE holds up better than its erosion in votes would suggest, and that the fragmentation of the right's vote hands it seats it does not win at the ballot box. The trackings used in the electoral analysis point to an excess of dead heats that would ultimately be settled in the smaller provinces, precisely where the quotient-based allocation decides.

The question that remains hanging is not how many votes change hands, but how many of those votes turn into seats. And there, the figure and the seat stop speaking to each other.