Barómetro electoral del CIS 2011 por provincias
El PSOE obtendría el peor resultado histórico: 116-121 diputados, con el 29,9%
3 min.
| ESTUDIO PREELECTORAL DEL CIS | 04/11/2011 | Resultado 2008 |
| CCAA | Provincia | Partidos | Escaños | Escaños |
| Andalucía | Almería | PSOE | 2 | 3 |
| | PP | 4 | 3 |
| Cádiz | PSOE | 3 | 5 |
| | PP | 5 | 4 |
| Córdoba | PSOE | 3 | 4 |
| | PP | 3 | 2 |
| Granada | PSOE | 2 | 4 |
| | PP | 5 | 3 |
| Huelva | PSOE | 2 - 3 | 3 |
| | PP | 2 - 3 | 2 |
| Jaén | PSOE | 3 | 4 |
| | PP | 3 | 2 |
| Málaga | PSOE | 3 | 5 |
| | PP | 7 | 5 |
| Sevilla | PSOE | 6 | 8 |
| | PP | 5 | 4 |
| | IU-ICV | 1 | - |
| Aragón | Huesca | PSOE | 1 | 2 |
| | PP | 2 | 1 |
| Teruel | PSOE | 1 | 2 |
| | PP | 2 | 1 |
| Zaragoza | PSOE | 3 | 4 |
| | PP | 4 | 3 |
| Asturias | Asturias | PSOE | 3 | 4 |
| | PP | 3 | 4 |
| | IU-ICV | 1 | - |
| Illes Balears | Illes Balears | PSOE | 3 | 4 |
| | PP | 5 | 4 |
| Canarias | Las Palmas | PSOE | 3 | 4 |
| | PP | 4 | 4 |
| | CC-NC | 1 | - |
| Santa Cruz de Tenerife | PSOE | 2 | 3 |
| | PP | 4 | 2 |
| | CC-NC | 1 | 2 |
| Cantabria | Cantabria | PSOE | 2 | 2 |
| | PP | 3 | 3 |
| Castilla y León | Ávila | PSOE | 0 - 1 | 1 |
| | PP | 2 - 3 | 2 |
| Burgos | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| León | PSOE | 2 | 3 |
| | PP | 3 | 2 |
| Palencia | PSOE | 1 | 1 |
| | PP | 2 | 2 |
| Salamanca | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| Segovia | PSOE | 1 | 1 |
| | PP | 2 | 2 |
| Soria | PSOE | 0 - 1 | 1 |
| | PP | 1 - 2 | 1 |
| Valladolid | PSOE | 2 | 2 |
| | PP | 3 | 3 |
| Zamora | PSOE | 1 | 1 |
| | PP | 2 | 2 |
| Castilla la Mancha | Albacete | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| Ciudad Real | PSOE | 2 | 2 |
| | PP | 3 | 3 |
| Cuenca | PSOE | 1 | 1 |
| | PP | 2 | 2 |
| Guadalajara | PSOE | 1 | 1 |
| | PP | 2 | 2 |
| Toledo | PSOE | 2 | 3 |
| | PP | 4 | 3 |
| Catalunya | Barcelona | PSOE | 11 | 16 |
| | PP | 8 | 6 |
| | IU-ICV | 3 | 1 |
| | CIU | 7 | 6 |
| | ERC | 8 | 2 |
| Girona | PSOE | 2 | 3 |
| | PP | 1 | - |
| | CIU | 2 | 2 |
| | ERC | 1 | 1 |
| Lleida | PSOE | 1 | 2 |
| | PP | 1 | 1 |
| | CIU | 2 | 1 |
| Tarragona | PSOE | 2 | 4 |
| | PP | 2 | 1 |
| | CIU | 2 | 1 |
| Ceuta | PP | 1 | x |
| Comunitat Valenciana | Alicante | PSOE | 4 | 5 |
| | PP | 8 | 7 |
| | FAC | 1 | - |
| Castellón | PSOE | 2 | 2 |
| | PP | 3 | 3 |
| Valencia | PSOE | 5 | 7 |
| | PP | 9 | 9 |
| | IU-ICV | 1 | - |
| | COMPROMÍS-EQUO | 1 | - |
| Extremadura | Badajoz | PSOE | 3 | 3 |
| | PP | 3 | 3 |
| Cáceres | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| Galicia | A Coruña | PSOE | 2 | 3 |
| | PP | 5 | 4 |
| | BNG | 1 | 1 |
| Lugo | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| Ourense | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| Pontevedra | PSOE | 2 | 3 |
| | PP | 4 | 3 |
| | BNG | 1 | 1 |
| La Rioja | La Rioja | PSOE | 1 | 2 |
| | PP | 3 | 2 |
| Madrid | Madrid | PSOE | 9 - 10 | 15 |
| | PP | 21 - 22 | 18 |
| | UPyD | 3 | 1 |
| | IU-ICV | | 1 |
| Melilla | Melilla | PP | 1 | x |
| Navarra | Navarra | PSOE | 2 | 2 |
| | PP | 3 | 2 |
| | NA-BAI | - | 1 |
| País Vasco | Álava | PSOE | 2 | 2 |
| | PP | 2 | 1 |
| | PNV | - | 1 |
| Guipúzcoa | PSOE | 2 | 3 |
| | PP | 1 | 1 |
| | PNV | 1 | 2 |
| | AMAIUR | 1 | - |
| Vizcaya | PSOE | 3 | 4 |
| | PP | 2 | 1 |
| | PNV | 2 | 3 |
| | AMAIUR | 1 | - |
| Murcia | Murcia | PSOE | 2 - 3 | 3 |
| | PP | 7 - 8 | 7 |