The citizens’ initiative Senadoras y Senadores por la Democracia has secured joint candidacies by left-wing parties for the 29 November 2026 in 43 provinces and 47 constituencies for the elections on Senate . According to consistent accounts from party sources and the media, participants include the PSOE, Izquierda Unida and several regional groups. The four Catalan provinces are excluded, where the PSC is taking account of a possible alliance with ERC , as are the Canary Islands, with the exception of La Gomera.
The immediate trigger is the overdue renewal, since December 2025, of four judicial posts on the Tribunal Constitucional, including that of its president Cándido Conde-Pumpido. These four seats are allocated to the Senate. Their appointment requires a three-fifths majority in the chamber. In the previous parliamentary term, the Partido Popular and the Mesa del Senado, which it dominated, blocked the renewal. If the right-wing bloc of Partido Popular and Vox manages to secure this qualified majority after 29 November 2026, it could appoint new judges to all four Senate seats on the Constitutional Court and shape the body’s ideological make-up for years. This is the main concern driving the new left-wing coordination.
Spanish Senate elections follow a majoritarian system at provincial level: four seats are directly elected in most provinces, and voters can cast several votes. In the past, separate left-wing lists have split the vote, allowing right-wing candidates to benefit disproportionately. The participating groups hope joint lists will limit this effect and increase the number of left-wing senators.
The initiative originated in civil society circles and was prepared unusually discreetly over several weeks. Official Senate announcements and the election calendar support the information on the deadline and the extent of the alliances. Representatives of the judiciary recently reiterated their appeal to parties not to delay further the renewals required by the Constitution in the justice system. The election outcome remains uncertain; the balance of forces nationwide and turnout in the provinces will be decisive.
Whatever the result, a three-fifths majority in the Senate will determine not only the four seats on the Tribunal Constitucional. It also carries considerable weight in appointments to the Consejo General del Poder Judicial, affecting institutional balances well beyond the current parliamentary term.
Editor: Phillipe Schmidt-Araguin (Article created with AI assistance).