PSOE drops nearly five points in first CIS poll after Zapatero indictment and Ferraz raid, but holds narrow lead over PP

The Socialist Party (PSOE) has suffered a sharp drop in voter support in the latest barometer from Spain's Centre for Sociological Research (CIS), published on Thursday. The poll, conducted between 1 and 4 June with 4,024 interviews, is the first to capture public reaction to two corruption investigations directly touching the party: the indictment of former prime minister José Luis Rodríguez Zapatero in the Plus Ultra case, and the reactivation of the so-called 'Leire Díez case', which saw Guardia Civil officers enter the PSOE's Ferraz headquarters.

The electoral arithmetic

The PSOE would still win a general election with 31.3% of the estimated vote, but that figure represents a fall of 4.9 points from the 36.2% recorded in the May barometer. The conservative People's Party (PP), led by Alberto Núñez Feijóo, gained 2.2 points to reach 27.1%, cutting the gap between the two main parties from 11.3 points to just 4.2 points. Vox remained in third place but slipped four-tenths of a point to 15.8%, continuing a downward trend that has seen the far-right party lose three points since February.

The judicial investigation into former president Zapatero has hit the PSOE like a missile.

The coalition and smaller parties

Sumar, the junior partner in the governing coalition, rose seven-tenths of a point to 6.4%, while Podemos gained three-tenths to 2.8%. The far-right party SALF, led by MEP Luis 'Alvise' Pérez, registered 1.9%. Among regional forces, ERC led with 1.9%, followed by EH Bildu at 1.2%, Junts at 1.0%, and the Galician BNG at 1.0%. The Basque PNV stood at 0.6%.

The corruption cases behind the shift

The fieldwork for the June barometer coincided with two major developments. On 19 May, National Court judge José Luis Calama indicted former prime minister Zapatero for alleged influence peddling and related offences, including criminal organisation, in connection with the €53 million government bailout of airline Plus Ultra during the pandemic. The judge described Zapatero as the leader of a "hierarchical and stable" organisation that allegedly used his contacts and access to senior officials to obtain illicit benefits.

The judge places the former president as the leader of a hierarchical and stable organisation to obtain benefits illicitly, leveraging his contacts and access to high-ranking administration officials.

A week later, on 27 May, the Central Operative Unit (UCO) of the Guardia Civil entered the PSOE's national headquarters on Ferraz street in Madrid, acting on an order from National Court judge Santiago Pedraz. The search sought documentation related to alleged payments by the party to a network that gathered information on judges, prosecutors, and members of the security forces. That investigation had already led to charges against Leire Díez, a former party official dubbed the 'PSOE plumber', and the party's former organisation secretary Santos Cerdán. When the court summary was released, Díez's diaries came to light, containing references that have further fuelled the scandal.

What worries Spaniards most

The CIS barometer also tracks the issues Spaniards consider the country's main problems. Housing remains the top concern for the eighteenth consecutive month, cited by 41.5% of respondents. The economic crisis follows at 19.2%, with immigration climbing to third place at 18.9%. Corruption and fraud, at 18.4%, and political problems in general, at 18.3%, round out the top five — a ranking that underscores the political salience of the investigations now buffeting the governing party.

Despite the steep decline, the PSOE retains a lead over the PP, and the combined left-of-centre vote — PSOE, Sumar, and Podemos — would still outpoll the right-of-centre bloc of PP, Vox, and SALF. But the seven-point collapse in the margin over the PP, from 11.3 points in May to 4.2 points in June, marks the narrowest gap recorded since the current legislature began, and places the Socialists in a more vulnerable position as the corruption cases continue to develop.