This dataset contains case-level quantitative and calibrated comparative data for 18 Spanish municipalities governed or contested by social movement-led left coalitions associated with the Spanish New Municipalist cycle. The data were assembled to support a fuzzy-set Qualitative Comparative Analysis (fsQCA) of the conditions associated with the electoral consolidation of these coalitions and with incipient urban regime contention. The unit of analysis is the municipality/case. The dataset brings together indicators on electoral performance, governing position, council seat shares, intergovernmental ideological allies, city size, fiscal capacity, capital mobility, and civic capacity. Variables are derived from official election results, municipal spending records, Eurostat Cities and Greater Cities data, Spanish National Institute of Statistics data, Spanish Ministry of the Interior protest statistics, official municipal government composition records, and official Autonomous Community electoral authorities. The dataset includes raw measures and/or coded indicators used to construct fuzzy-set scores for comparative analysis.

This dataset compiles comparative information on Spanish municipal politics (gathered as part of Marie Sklodowska Curie Actions Project 101106701) to analyse the conditions under which municipalist political projects achieve electoral and institutional consolidation in the period after 2015. It integrates data from multiple official sources at the European, national, and regional levels, complemented by information collected directly from municipal and regional government websites. The dataset combines structural indicators—such as capital mobility, fiscal capacity, and population size—with political, institutional and behavioural variables, including electoral turnout, protest activity, vote shares, and governing positions. These variables are operationalised using harmonised measures derived from administrative records, electoral results, and statistical datasets, ensuring comparability across cases and over time. In addition to descriptive indicators, the dataset includes constructed variables that capture relational and contextual dynamics, such as intergovernmental ideological alignment and patterns of government formation. Where necessary, raw data have been standardised and aggregated across electoral cycles (2015, 2019, and 2023) to facilitate longitudinal comparison. Overall, the dataset is designed to support configurational and comparative analysis, enabling the examination of how different combinations of socio-economic and political conditions shape trajectories of municipal political change.

METHODOLOGICAL INFORMATION

1. Description of methods used for collection-generation of data:

The dataset was generated for a comparative analysis of 18 Spanish municipalities associated with the New Municipalist cycle after the 2015 local elections. Cases were selected as municipalities in which social movement-led left coalitions entered local electoral competition and attempted to consolidate a governing or oppositional foothold in urban politics. The dataset combines publicly available quantitative indicators with theoretically informed coding decisions. Data were collected from official electoral sources, statistical agencies, municipal records and administrative databases.

The outcome, electoral consolidation of social movement-led left coalitions, is operationalised through electoral victory/government formation in 2019 and/or 2023, average vote share across 2015, 2019 and 2023 municipal elections, and governing position across the 2015, 2019 and 2023 terms. The broader condition set captures economic, political-institutional, civic and demographic characteristics of the cases.

Economic conditions include capital mobility, proxied through the percentage of the workforce in finance and professional work, and fiscal capacity, proxied through average municipal spending per capita from 2015 to 2019. Civic capacity combines provincial protest per capita, average municipal election turnout and average general election turnout. Political-institutional conditions include average council seat share and the presence of intergovernmental ideological allies at the Autonomous Community level. City size is measured through 2015 municipal population.

The full calibration rationale is documented in the methodological appendix to the related publication, which is also attached here.

Bua, A. (2026). The politics of urban regime contention: A Qualitative Comparative Analysis of 18 Spanish cases. Urban Studies. Online First. https://doi.org/10.1177/00420980251405755

1. Methods for processing the data:

The submitted data were generated by compiling raw case-level indicators from official sources and transforming them into comparable measures for fuzzy-set Qualitative Comparative Analysis. Processing steps included:

• harmonising case names and municipal identifiers across different sources;
• calculating averages across elections or legislative terms where variables refer to repeated observations;
• converting vote shares, council shares and turnout indicators into proportions or percentages as appropriate;
• aggregating provincial protest statistics into protest-per-capita indicators;
• calculating average municipal spending per capita for 2015-2019;
• using Eurostat Cities and Greater Cities data for finance and professional employment, with distance-based adjustment for municipalities located within larger urban areas where municipal-level data were not available;
• coding governing position and intergovernmental ideological allies using documented ordinal/fuzzy-set coding schemes;
• applying calibration thresholds to produce fuzzy-set scores where required for QCA.

Some indicators are measured at higher spatial scales than the municipality because equivalent reliable municipal-level data were unavailable. Protest data are provincial. Finance and professional workforce data are based on Eurostat Cities and Greater Cities areas, with adjustments for municipalities located outside the central municipality of the functional urban area. Intergovernmental allies are coded at the Autonomous Community level.

1. Instrument- or software-specific information needed to interpret the data:

The dataset is provided both as a CSV and as a Microsoft Excel workbook (.xlsx). It can be opened with Microsoft Excel, LibreOffice Calc, Google Sheets or other spreadsheet software supporting .xlsx files. The data can also be imported into statistical and comparative-methods software such as R, Python, Stata, SPSS, fsQCA or Tosmana after conversion to .csv or another preferred tabular format.

No proprietary analytical software is required to interpret the variables. Users wishing to reproduce the fuzzy-set QCA analysis should use software capable of fsQCA truth-table minimisation and consistency/coverage calculations.

1. Instruments, calibration and standards information:

The dataset uses fuzzy-set calibration scores ranging from 0 to 1, where higher scores indicate stronger membership in the relevant set. Calibration thresholds were determined using theoretically informed qualitative anchors and relevant Spanish averages where appropriate. The calibration schemes cover electoral consolidation, capital mobility, fiscal capacity, civic capacity, council/parliamentary position, intergovernmental ideological allies and city size.

Key calibration conventions include:

• Electoral consolidation combines a binary indicator of electoral victory/government formation in 2019 and/or 2023, average vote share, and average governing position.
• Capital mobility uses finance and professional workforce as a proxy for exposure to mobile capital and high-value networked services.
• Fiscal capacity uses average municipal spending per capita from 2015 to 2019.
• Civic capacity averages calibrated scores for protest per capita, municipal election turnout and general election turnout.
• Council position uses the average proportion of council seats held by the municipalist candidacy across 2015, 2019 and 2023.
• Intergovernmental ideological allies are coded by the ideological affinity of the Autonomous Community government with social movement-led left coalitions, combining left-right economic ideology and national identity/plurinational affinity.
• City size uses 2015 municipal population.

The associated methodological appendix provides the detailed thresholds and coding rationale.

1. Environmental or experimental conditions: Not applicable. The dataset was generated from secondary public administrative, electoral and statistical data. No experimental, laboratory, fieldwork-environmental or atmospheric conditions apply.

2. Quality-assurance procedures performed on the data: Coding decisions for ordinal and fuzzy-set indicators are documented in the methodological appendix to support transparency and reproducibility.