Will PSOE win the most seats in the 2026 Spanish general election?

- [2026-10-05] Sánchez announced a snap general election for Sunday 29 Nov 2026. Real Decreto 806/2026 dissolves the Cortes, and the BOE publication was due 6 Oct. The trigger was Congress rejecting two housing decrees on 2 Oct, amid housing protests. https://www.lamoncloa.gob.es/presidente/actividades/paginas/2026/051026-sanchez-convocatoria-elecciones.aspx - [2026-10-06 to 2026-10-19] Electoral calendar (Wikipedia, ES): candidacies proclaimed 2 Nov, published in the BOE 3 Nov, campaign 13–27 Nov, postal voting 10–25 Nov, vote 29 Nov. That leaves one day between the vote and the 30 Nov trading close. https://es.wikipedia.org/wiki/Elecciones_generales_de_Espa%C3%B1a_de_2026 - [2026-10-17] Poll averages, with PP first and PSOE second in every private aggregate: - PolitPro: PP 31.9%, PSOE 26.6%, Vox 18.8%, a 5.3-point lead. - El Periódico aggregate: PP 133 seats, PSOE 111, Vox 68. - Europa Press average (16 Oct): PP 31.3%, PSOE 27.1%, a 4.2-point lead. - elDiario.es (15 Oct): PP 135, PSOE 106. - RTVE (14 Oct): PP 136, PSOE 106. https://en.wikipedia.org/wiki/2026_Spanish_general_election - [2026-10-11] Sigma Dos/El Mundo: PP 135 seats (31.9%), PSOE 103 (25.3%), Vox 68 (19.1%). https://en.ara.cat/politics/what-do-the-polls-for-the-spanish-elections-of-november-29th-say_1_5874100.html - [2026-10-11] SocioMétrica poll: PP 32.6%, PSOE 26.2%, Vox 18.8%. https://politpro.eu/en/spain - [2026-10-08] 40dB/El País-SER (fieldwork 7–8 Oct) is the best private poll for PSOE: PP 31.9%, PSOE 28.1%, and seats PP 132, PSOE 112, Vox 66. PP+Vox total 198, above the 176 majority. https://en.ara.cat/politics/what-do-the-polls-for-the-spanish-elections-of-november-29th-say_1_5874100.html - [2026-10-08] GESOP/El Periódico (fieldwork 6–8 Oct) has the narrowest gap in the legislature. PP leads by 2.6 points (28.7% vs 26.1%), with seats PP 121–125 and PSOE 108–112. GAD3 (fieldwork 8 Oct) has PP 133 seats and PSOE 107, with PP 31.4% and PSOE 26.4%. https://en.ara.cat/politics/what-do-the-polls-for-the-spanish-elections-of-november-29th-say_1_5874100.html and https://www.democrata.es/en/center-of-surveys-and-electoral-polls/general-elections/general-elections-survey-pp-and-vox-lose-four-seats-but-maintain-198-compared-to-the-107-of-psoe-according-to-gad3/ - [2026-10-14] The CIS October barometer is the outlier. It has PSOE 34.0%, PP 22.2% and Vox 17.1%, an 11.8-point PSOE lead. Fieldwork predates the election call. Private pollsters contradict it. https://www.infobae.com/espana/2026/10/14/ha-salido-el-cis-el-psoe-ganaria-las-elecciones-generales-con-mas-de-5-puntos-sobre-el-pp-y-vox-se-hunde-al-117/ - [2026-10-14] Catalan CEO barometer (fieldwork 1 Sep–5 Oct): PSC would be first in Catalonia with 18–19 seats. ERC is second with 10–11. https://en.ara.cat/politics/what-do-the-polls-for-the-spanish-elections-of-november-29th-say_1_5874100.html - [2026-10-17] The left is still fragmented. Sumar parties launched the "Broad Front" platform, led by Ada Colau. Podemos has an agreement with ERC (Rufián to campaign with Podemos outside Catalonia). That split could cost the left seats. Only PSOE seats count for this market. https://en.wikipedia.org/wiki/2026_Spanish_general_election - [2026-10-05] Spanish seat baseline from the 2023 election: PP 137, PSOE 121, Vox 33. No private poll in the last two weeks has PSOE ahead of PP in seats. https://en.wikipedia.org/wiki/2026_Spanish_general_election - [2026-10-19] The resolution source (infoelectoral.interior.gob.es) cannot show results before the 29 Nov vote. I did not open it. BOTTOM LINE: The election is confirmed for 29 Nov 2026, and PP leads PSOE in every private poll since the call by about 2.6–7 points and roughly 20–35 seats. The CIS is the only poll with PSOE first, and PSOE's best private result is 40dB at 112 seats against PP's 132. Two caveats: the vote falls one day before the market's trading close, and the Interior Ministry will publish results the night of the vote. NOT FOUND: any post-call Spanish poll with PSOE ahead of PP in seats apart from the CIS; official Interior Ministry candidate lists (due 2–3 Nov); polls fielded after 14 Oct that capture campaign effects.

- [2026-10-05] Sánchez dissolved parliament and called a general election for 29 Nov 2026. The election is about 6 months ahead of schedule. It followed the defeat of two housing decrees, which PP, Vox and Junts voted down. Campaign is expected to start 13 Nov. https://edition.cnn.com/2026/10/05/europe/spain-leader-calls-snap-election-intl-hnk ; https://www.theportugalnews.com/news/2026-10-06/sanchez-calls-snap-election-in-spain/1096413 - [2026-10-18] The PolitPro weighted average puts PP at 31.9% and PSOE at 26.6%, a 5.3-point PP lead. Vox is rising. https://politpro.eu/en/spain - [2026-10-17] Latest EM-Analytics/Electomanía poll (15–17 Oct, n=3,141, after the left-pact "Broad Front" was formed): PP 31.8% (134 seats), PSOE 27.1% (111), Vox 18.9% (62). The gap is 4.7 points. https://en.wikipedia.org/wiki/Opinion_polling_for_the_next_Spanish_general_election - [2026-10-06 to 10-11] Nearly all private polls show PP ahead in both vote and seats. Seat leads for PP over PSOE: - NC Report: 146–148 vs 98–102. - Sigma Dos (1–8 Oct): 135 vs 103. - GAD3: 133 vs 107. - 40dB/Prisa: 123–140 vs 105–117 (its closest private poll, 3.8-point vote gap). - GESOP: 121–125 vs 108–112. - IMOP: 130 vs 110. https://en.wikipedia.org/wiki/Opinion_polling_for_the_next_Spanish_general_election ; https://www.democrata.es/en/center-of-surveys-and-electoral-polls/general-elections/general-elections-survey-vox-gains-five-seats-the-pp-loses-five-and-the-psoe-stagnates-at-103-according-to-sigma-dos/ - [2026-10-01 to 10-06] The state CIS is an outlier. Its Opina 360 poll gives PP 28.0% (119 seats) vs PSOE 28.0% (118), a tie. Its Ateneo del Dato version gives PSOE 28.6% (116) vs PP 28.3% (119). A PSOE-commissioned poll (5 Oct, n=7,000) showed PSOE 129 vs PP 126. A SocioMétrica poll commissioned by PP showed PP 144 vs PSOE 106. Partisan commissioning is a caveat. https://en.wikipedia.org/wiki/Opinion_polling_for_the_next_Spanish_general_election - [2026-10-11] Sigma Dos/El Mundo: PP 135, PSOE 103, Vox 68. PP+Vox total 203 seats, against 114 for PSOE+Sumar+Podemos. PSOE is 18 seats below its 2023 result. https://www.democrata.es/en/center-of-surveys-and-electoral-polls/general-elections/general-elections-survey-vox-gains-five-seats-the-pp-loses-five-and-the-psoe-stagnates-at-103-according-to-sigma-dos/ - [2026-10-05] Olive Press average of eight polls: PP 33.3% vs PSOE 25.7%. The polls predate the snap call. https://www.theolivepress.es/spain-news/2026/10/05/who-will-win-spains-snap-election-on-november-29-and-what-do-the-five-main-parties-stand-for/ - [2023-07-23] Reference-class caution from the 2023 election. Polls had suggested a PP landslide, but PP won only 137 seats vs PSOE 121, with 33% vs 31.7% of the vote. PSOE beat expectations by a few points, though PP still won the most seats. PSOE's poll shortfall was larger this time. https://es.statista.com/estadisticas/1401393/elecciones-generales-de-espana-2019-2023-escanos-por-partido - [2019] Sánchez has called snap elections before. In 2019 PSOE led polls (~30%) and won 123 seats (Apr) and 120 (Nov). In 2023 he called a snap election after local-election losses and PSOE finished second. So the base rate for his snap calls is mixed: PSOE first in 2019 (twice), second in 2023. https://www.pressreader.com/suriname/times-of-suriname/20190216/282123522777078 ; https://es.statista.com/estadisticas/1378251/elecciones-generales-de-espana-2019-porcentaje-de-votos-por-partido-abril-y-noviembre - [2026-10-17] Polymarket's separate "Spain General Election Winner" event (as of 17 Oct) shows PP and PSOE as the two outcomes. Its page says PP polling leads of about 5 points are consistent with the other sources here. https://polymarket.com/event/spain-general-election-winner - [2025–2026] Sánchez repeatedly promised elections in 2027, so the Oct 2026 call is a reversal. Prior spontaneous elections ran about 54 days from decree to vote, so a vote on 29 Nov is formally on schedule. Results are normally known on election night, with Interior ministry results within days, well before the 30 Nov 2027 deadline. https://www.theportugalnews.com/news/2026-10-06/sanchez-calls-snap-election-in-spain/1096413 ; https://www.ceutaactualidad.com/articulo/nacional-internacional/sanchez-descarta-adelanto-electoral-elecciones-2027/20260619171316273938.html - [2023-07-23] Historical note: PP has won the most seats in every Spanish general election since 2023 only once (2023). PSOE won 2019 (both) and 2023's runner-up status shows seat-leader outcomes track national vote lead. In 2023 the final-week polling lead for PP was ~5–10 points and the realized lead was ~1.3 points, which is a sizeable historical miss in PSOE's favour. https://es.statista.com/estadisticas/1401360/elecciones-generales-de-espana-2019-2023-porcentajede-votos-por-partido BOTTOM LINE: The outside view is that PP leads in virtually all private polls, by about 4–8 points and 20–40 seats. Only the CIS and PSOE-commissioned polls show a tie or a PSOE lead, and the 2023 poll miss (PSOE beat polls by several points) is the main reason not to treat PP as certain. A PSOE seat win would require an error larger than the typical lead, though a roughly 4–5-point gap in the closest polls is within historical Spanish polling error. NOT FOUND: An official Interior ministry/infoelectoral pre-election projection (none exists). Independent betting odds beyond Polymarket (not searched, per instructions). Post-Broad Front polls besides Electomanía's. A track-record table of Spanish pollsters (only the 2023 miss is documented here). One bullet above ("PP has won the most seats in every election since 2023 only once") is garbled. Disregard it; the correct reading is that PP won the most seats in 2023 and PSOE won in 2019 (both).

YES means: PSOE (including PSC) wins more Congress seats than any other party, with the tie-break on nationwide votes, in the 29 Nov 2026 election. - [2026-10-14] The CIS October barometer (study 3582, 5,025 interviews, fieldwork 1–6 Oct) is the only post-call poll with PSOE first. It has PSOE 34.0% against PP 22.2% and Vox 17.1%, an 11.8-point lead. The CIS has no official seat projection. Electomanía converted it into PSOE 152, PP 94 and Vox 63. The September CIS had PSOE 31% and PP 25.5%, so the October figure is a 3-point PSOE rise and a 3.3-point PP fall. Sources: https://electomania.es/barometro-del-cis-oct26-la-izquierda-se-dispara-con-el-psoe-en-el-34/ ; https://www.cmmedia.es/noticias/espana/barometro-cis-octubre-2026-psoe-pp-vox.html - [2026-10-14] The CIS stated its direct vote intention before any modelling: PSOE 25.3% of the census against PP 14.7%. So the PSOE lead appears in the raw answers as well as in the CIS "cooking". Caveat: private pollsters put PSOE at about 25–26%. Source: https://www.canariasenpleno.com/elecciones-generales-2026-cis/ - [2026-10-14] In the CIS, the parties that backed Sánchez's investiture total 50.6%. PP, Vox and UPN total 39.4%. If this block gap is real, PSOE wins on seats as well. Source: https://www.thespanisheye.com/2026/10/14/major-rebound-for-pedro-sanchez-as-new-poll-gives-the-psoe-an-almost-12-point-lead/ - [2026-10-06] The most likely path to YES is a 2023-style late rally. In 2023, polling averages gave PP and Vox a majority, and that did not happen. PSOE then raised its vote share. A political scientist in The Conversation says the right's lead is larger this time. He also points to three PSOE-friendly mechanisms. (1) Housing is now the agenda. (2) Left voters may vote tactically for PSOE, especially if the parties to its left stay divided. (3) The prospect of a PP–Vox government may mobilise the left. Source: https://theconversation.com/spains-snap-election-will-pedro-sanchezs-latest-gamble-pay-off-293716 - [2026-10-17] Prerequisites for the rally path. PSOE must gain about 4–5 points on the private-poll average, which Demócrata puts at PP 31.3% against PSOE 27.1%. Demócrata's check without the CIS widens the PP lead to 5.7 points. Vox's gains must also stay at PP's expense rather than PSOE's: in the Vozpópuli poll, 12.9% of 2023 PP voters now say Vox, against 2.9% of Vox voters moving to PP. Sources: https://www.democrata.es/encuestas/elecciones-generales/queda-promedio-encuestas-generales-fracaso-pacto-izquierdas-pp-vox-rozan-50/ ; https://www.vozpopuli.com/espana/politica/debacle-de-la-izquierda-pp-y-vox-suman-ya-212-escanos-y-el-53-de-los-votos.html - [2026-10-17] The Demócrata average notes that "part of the benefits" of the left's split can stay with PSOE. Its polls predate the failed left pact, so they do not measure the reaction to it. If voters of Sumar and Podemos defect to PSOE, the gain is PSOE-only. Source: https://www.democrata.es/encuestas/elecciones-generales/queda-promedio-encuestas-generales-fracaso-pacto-izquierdas-pp-vox-rozan-50/ - [2026-10-17] The Objective's Votómetro (Redlines) shows PSOE narrowing the gap slightly. Even so, it gives PP+Vox a joint range of 198–216 seats and a 98.9% chance of a PP–Vox government. For this market the useful point is that the PSOE-narrowing trend is visible in a right-leaning outlet. The same model rules out PSOE governing, which is a separate question from first place. Source: https://theobjective.com/espana/politica/2026-10-17/votometro-pp-vox-mayoria-absoluta-psoe-izquierda/ - [2026-10-18] Seat-lead mechanics. In the GESOP range (PP 121–125, PSOE 108–112), the best PP–PSOE gap is about 9–17 seats. The gap is smallest where PSOE does best in provincial small-seat contests. The Sigma Dos regional projection has PSOE at parity with PP in Asturias, the Canaries and Cantabria. It also has PSOE winning Catalonia with 16 seats, Navarre and the Basque Country. A uniform PSOE swing in those places could cut the gap quickly. Sources: https://www.democrata.es/en/center-of-surveys-and-electoral-polls/general-elections/29n-by-communities-vox-advances-and-the-psoe-retreats-in-the-autonomous-map/ ; https://elecciones29noviembre.com/encuestas/ - [2026-10-17] The Jacobin-style assessment (Yahoo, ~10 Oct) is that Sánchez is betting on housing protests and a planned early-November general strike to reset the agenda. Ceuta is the other pressure point. This is commentary, not data. Source: https://www.yahoo.com/news/politics/articles/pedro-nchez-makes-last-gamble-124034566.html - [2026-10-18] Sánchez opened the pre-campaign on 17 Oct with a mobilisation message built on pensions ("cuts disguised as sacrifices") and housing. Begoña Gómez, awaiting trial, attended. The report says the polls place PSOE "far from" a parliamentary majority, which is a different bar from first place. Source: https://www.democrata.es/en/politics/sanchez-activates-the-pre-campaign-and-calls-for-mobilization-against-the-chainsaw-to-pensions/ - [2026-10-17] PolitPro's election-win probability is a model output, not an observation. It gives PSOE 2% and PP 98%. It is the only quantified PSOE chance I found, and it is very low. Source: https://politpro.eu/en/spain/election/parliament/2026 BOTTOM LINE: The strongest YES case is a 2023-style late left mobilisation, with housing and a PP–Vox-government scare, on top of the CIS and the tactical-vote mechanics, to close a 4–5-point private-poll gap. Every private seat projection I found still has PP ahead by roughly 9 to 40 seats, so this path needs a polling miss larger than the 2023 one. NOT FOUND: any private post-call poll with PSOE ahead on seats. No official CIS seat projection. No polls fielded after the 17 Oct left-pact failure beyond Electomanía. No pollster-accuracy track record for 2023. Candidate lists are not yet proclaimed (due 2 Nov).

YES means: PSOE (including PSC) wins strictly more Congress seats than any other party on 29 Nov 2026, with ties broken by votes. The case below argues for NO. - [2026-10-17] Poliwave's seat model gives PP a 97% chance of the most seats and PSOE 2%. Its projection is PP 141 (range 123–155) against PSOE 107 (range 90–121), with a median gap of about 33 seats. The model's own 95% intervals barely overlap. https://www.poliwave.com/es/gen/projection - [2026-10-17] The Objective/Redlines Votómetro, the first one after the call, has PSOE at 26.6% and 101–110 seats, unchanged from the previous edition. It has PP at 32.2% with a best case of about 145 seats. It weights pollsters by historical bias and house effects and runs 10,000 simulations. Its upper PSOE bound (110) sits below the PP lower bounds in most polls. The same source says PSOE voter loyalty is only 65.9%. https://theobjective.com/espana/politica/2026-10-17/votometro-pp-vox-mayoria-absoluta-psoe-izquierda/ - [2026-10-10] Vote-Scope's province-by-province model has PP 134 (range 120–149) and PSOE 106 (range 93–120). The highest PSOE seat count in any range is 120, below the PP midpoint. Its Orbit model's widest PSOE range (82–136) overlaps PP's (102–160) but still has PP ahead at the median. https://vote-scope.com/en/spain/ - [2026-10-17] Sigma Dos's regional breakdown shows how the seat gap arises. PP leads in Andalucía (25 vs 17), Madrid (16 vs 9), Galicia (15 vs 6), Castilla y León (16 vs 8) and the Valencian Community (12 vs 10). PSOE's only large lead is Catalonia, at 16 seats. For PSOE to overtake PP it would need to win several of these big regions, not just narrow the national vote gap. https://www.sigmados.com/sondeo-de-arranque-de-campana-estimacion-de-voto-para-las-elecciones-generales-29-n-por-comunidad-autonoma/ - [2026-10-12] The GAD3 survey for ABC shows PSOE up only 0.3 points since September (26.4%), with PP also up 0.3 (31.4%). PSOE is up 2 seats to 107 and PP is flat at 133. The call has not produced a PSOE bounce relative to PP in the polls that fielded after it. https://www.democrata.es/en/center-of-surveys-and-electoral-polls/general-elections/general-elections-survey-pp-and-vox-lose-four-seats-but-maintain-198-compared-to-the-107-of-psoe-according-to-gad3/ - [2026-10-15] The Demócrata average of 16 institutes, updated 15 Oct, has PP 31.7%, PSOE 26.8% (4.9-point gap), and PP+Vox on 204 seats. It puts PP 33 seats ahead of PSOE. https://democrata.es/en/center-of-surveys-and-electoral-polls/the-average-of-democratic-polls-places-the-pp-almost-five-points-above-the-psoe-and-pp-and-vox-at-204-seats - [2026-10-19] The closest private poll is GESOP, with PP leading by 2.6 points (28.7% vs 26.1%). Its PP figure is 3.5 points below a six-poll reference average. That makes GESOP an outlier on PP's weakness rather than evidence of a PSOE surge, since PSOE's own figure matches the average within a tenth of a point. Even so, GESOP's seat ranges (PP 121–125, PSOE 108–112) do not touch. https://www.democrata.es/encuestas/elecciones-generales/encuesta-elecciones-generales-psoe-queda-26-puntos-pp-pero-vox-sostiene-mayoria-derecha-segun-gesop/ - [2026-10-17] The Sumar/Podemos split costs the left seats under D'Hondt. Vote-Scope puts Sumar and Podemos on 9 seats if they run apart and 19 if they run together. That is a 10-seat gap, but it does not help this market because only PSOE seats count. There is no PSOE-seat upside from left unity, and PSOE's own voter loyalty is weak. https://vote-scope.com/en/spain/ and https://theobjective.com/espana/politica/2026-10-17/votometro-pp-vox-mayoria-absoluta-psoe-izquierda/ - [2026-10-17] The only post-call evidence of damage to PP is the "caso Maricarmen". It lowered PP voter loyalty from 80% to 72%. Vox absorbed the loss: Vox is at 18.3% and rising, so PP's share held at 32.2%. PP's weakness is leaking to its right, which keeps PP+Vox above 198 seats but does not transfer to PSOE. https://theobjective.com/espana/politica/2026-10-17/votometro-pp-vox-mayoria-absoluta-psoe-izquierda/ - [2026-10-14] The CIS is the only poll with PSOE first. Infobae notes its fieldwork predates both the dissolution and the Maricarmen death. It is also contradicted by the post-event 40dB poll, which gave PSOE only seven tenths of a point of improvement. The CIS has a known pro-PSOE house effect, and the 2011 precedent shows the CIS pre-election poll had PP at 190–195 seats, in line with the final result. https://www.infobae.com/espana/2026/10/14/ha-salido-el-cis-el-psoe-ganaria-las-elecciones-generales-con-mas-de-5-puntos-sobre-el-pp-y-vox-se-hunde-al-117/ - [2026-10-05] Time left: 41 days from 19 Oct to the vote, with the campaign running only 13–27 Nov. Spanish snap-election campaigns are short and PP's lead has been stable at about 5 points since July. The Poliwave seat series moved PP from 127 to 143 and PSOE from 112 to 108 between 10 Jul and 19 Sep. The trend since July has been against PSOE, not for it. https://www.poliwave.com/es/gen/projection - [2023-07-23] The 2023 miss does not change the outcome. Final-week polls had PP far ahead and PP still finished first with 137 seats against PSOE's 121. A PSOE overperformance of that size would not be enough now: the current seat gap is about 25–35, against 16 in 2023. https://es.statista.com/estadisticas/1401393/elecciones-generales-de-espana-2019-2023-escanos-por-partido BOTTOM LINE: Every post-call private poll and every seat model has PP ahead by roughly 20–35 seats. The only seat model with an explicit probability (Poliwave, 17 Oct) puts PSOE winning the most seats at about 2%. PSOE would need a polling error well beyond the 2023 miss and a swing in several large regions, with no sign of either so far. NOT FOUND: any post-call poll other than the CIS with PSOE ahead in seats. Any evidence of a PSOE campaign bounce relative to PP. Poliwave's accuracy page on its past forecast errors, which I did not open. Any poll fielded after 17 Oct.