The PSOE and parties to its left are rushing an agreement in several provinces to try to dispute the absolute majority of the Senate to the PP

The Spanish Socialist Workers' Party (PSOE) and leftist parties are pushing for an agreement in several provinces to challenge the Popular Party's (PP) absolute majority in the Senate. With time running out, the PSOE and left-wing forces are accelerating negotiations to run together in key regions, aiming to consolidate progressive votes and deny the PP the seats needed to maintain its dominance in the upper house. Prime Minister Pedro Sánchez, speaking from Brussels, indicated all options remain open, including forming a joint candidacy with other leftist groups. Negotiations appear to be progressing positively, with both sides expressing optimism about reaching a deal. The political stakes are high. The PP began the legislative term with 143 senators and has used this majority as leverage against the government. Socialists estimate that a unified candidacy could shift the balance of power in the Senate, potentially leaving the PP below the 134 seats required for an absolute majority. Some socialist senators suggest the outcome might resemble the 2019 composition, where the PSOE would have more senators than the PP, though still lacking an outright majority. The strategy hinges on how senators are elected in provincial constituencies. Typically, four seats are allocated per province, with voters selecting three candidates. Usually, the most-voted list secures three seats, while the second-place list gets one. Other lists often receive none. A joint candidacy would allow leftist parties to pool their votes under common names, increasing their chances of securing these seats, which they risk losing if divided. Socialist sources claim the agreement is well underway, describing the talks as moving forward with positive momentum. Sánchez has publicly endorsed the possibility, although discussions continue and the approach will vary by constituency. The negotiations have been coordinated at the federal level by the PSOE and centralized by the Frente Amplio. Potential areas include northern provinces such as Asturias, Álava, and Navarra, as well as the Valencian Community, Extremadura, the Balearic Islands, and several Andalusian provinces, including Cádiz. Parties have until midnight on Friday, October 16, to announce electoral alliances. Candidate lists will be submitted between October 21 and 26, giving them some flexibility before finalizing their rosters. The move also carries institutional implications. The outcome of the negotiations could influence the balance of power in the Senate, particularly given the PP’s current control over the chamber. The PSOE is working on an internal report suggesting a united leftist list could secure 129 elected senators out of 209 currently up for election, surpassing the PP’s absolute majority threshold of 134. This projection is based on recent polling data and historical results, indicating that a unified list could give the left five additional senators in certain provinces, including La Rioja, Gipuzkoa, Navarra, Murcia, and Zamora. According to the report, if the PSOE, Frente Amplio, and Podemos field a combined list, they could win 129 elected seats, bringing their total to 150 when including those already designated by autonomous communities. This would push the left past the 134-seat threshold, denying the PP an absolute majority. Without a unified list, the Senate would likely see a near-tie between the PP and the PSOE, with the right-wing bloc maintaining the majority through existing appointments. A unified list would significantly alter the landscape, allowing the PSOE and its allies to take the lead in 11 provinces, gaining 22 additional seats. It would also break nine ties in the PSOE’s favor and secure extra seats in Mallorca, La Rioja, Navarra, Soria, Lleida, A Coruña, and Almería. The PSOE would retain its seats in Ibiza and Formentera, which it might otherwise lose to the PP. Overall, the potential impact of a unified candidacy is substantial, reshaping the political dynamics of the Senate.