Fact check: List of the 50 largest US cities by population (2020 census or 2023 estimates) and their mayoral party affiliations

1. What the datasets actually claim — the partisan headline and why it matters

The various analyses in the packet converge on a basic headline: mayoral offices in the nation’s largest cities are predominantly held by Democrats, with Republicans and independents representing a minority. The Wikipedia-derived list dated November 5, 2025 reports that among the 50 largest cities by recent population estimates, 39 mayors are Democrats, 8 are Republicans, and 3 are Independents, providing a straightforward partisan tally for that cohort ^[1]. Ballotpedia’s broader treatment of the 100 largest cities shows a similar Democratic advantage but different totals—reflecting scope differences and election outcomes through 2025—which illustrates that party distribution depends on the city sample selected and the cut-off date for counting mayors ^{[2] [3]}. This matters because comparing “50 largest” vs “100 largest” or using 2020 Census counts vs 2022 estimates shifts which municipalities are included and therefore the partisan composition.

2. Conflicting baselines: 2020 Census vs 2022/2023 estimates and the impact on rankings

The sources use two different population baselines: a 2020 Census ranking and a 2022 population estimate ranking, and those choices change city placement on a 50-city list. The Ballotpedia materials and a separate “top 50” compilation draw on 2020 and later estimates, but the Wikipedia list referenced in the packet specifically uses 2022 estimates in its November 2025 snapshot to rank the 50 largest cities ^{[4] [1]}. Because municipal populations shift and some large municipalities are consolidated city-counties (Honolulu, Indianapolis, Jacksonville, Louisville, Nashville), the ranking method affects which jurisdictions are included on a 50-city list and therefore affects the partisan totals. Any definitive list must state which population base it uses and note consolidated governments where the mayor’s electorate covers multiple jurisdictions ^[1].

3. Nonpartisan elections and the hidden layer in party tallies

A significant methodological caveat across the materials is that many large-city mayoral elections are officially nonpartisan, even when officeholders have known party affiliations; the datasets identify partisan leanings based on public record, endorsements, or prior party activity ^{[2] [3]}. Ballotpedia’s methodology includes identifying party affiliation where it is publicly stated or evident, but it also flags jurisdictions where officeholders are formally nonpartisan. That means a raw partisan count (e.g., 39 Democrats) mixes two phenomena: formal party-labeled offices and nonpartisan offices where mayors are nevertheless aligned with a party. Users should therefore treat the partisan totals as a measure of de facto political alignment, not a strict indicator of the legal partisan status of each office ^{[3] [1]}.

4. Year-over-year shifts and what election cycles changed the numbers

The supplied analyses document shifts in mayoral partisanship from 2016 through 2025 and report specific 2023 and 2025 election effects: Ballotpedia shows changes in several cities that produced modest net gains and losses across parties, and the 100-city tally in late 2025 lists 66 Democrats and 23 Republicans (plus minor-party and nonpartisan mayors), illustrating ongoing volatility ^{[2] [5]}. Municipal elections in 2023 affected 29 of the top 100 cities and altered party control in a handful, while 2025 contests mentioned in the sources further adjusted the partisan map. These dynamics explain why different snapshots (2023 analysis vs November 2025 snapshot) yield different totals and underscore the need for timestamped lists when citing mayoral party composition ^{[5] [2]}.

5. Evidence gaps, reliability limits, and how to interpret the original claim

The original request—“List of the 50 largest US cities by population (2020 census or 2023 estimates) and their mayoral party affiliations”—is feasible and is largely fulfilled by the studied sources, but with clear limitations: sources use different population bases, some mayoralties are legally nonpartisan, and two datasets (50-city vs 100-city) produce different summary counts. The most precise available summary in the packet gives 39 Democrats, 8 Republicans, 3 Independents for the 50 largest cities based on post-2020 estimates ^[1]. For authoritative use, one must specify whether the ranking uses the 2020 Census or 2022/2023 estimates and whether party labels represent formal ballot designations or inferred political affiliation ^{[4] [3]}.

6. Practical next steps for verification and transparent presentation

To produce a defensible published list, compile a timestamped 50-city ranking using a single population source (explicitly cite 2020 Census or a named estimate), list each mayor with the date of the confirmation, and annotate whether the office is officially nonpartisan or the affiliation is inferred; the packet’s Wikipedia and Ballotpedia entries provide proximate data and methodologies for those annotations ^{[1] [3]}. If you need a ready-to-publish table, use the 2022/2025-ranked 50 list as the basis and append Ballotpedia’s partisan attribution methods to each entry so readers understand the scope, timing, and caveats behind the partisan tallies ^{[1] [2]}.