Sources & methods
Every number on this site traces back to one of these public sources. Each chart's “Sources & methods” button, and every clickable mark, shows the exact files, versions, arithmetic and individual filings behind it.
How the data is handled
- Raw files and API responses are stored exactly as received, with their download time, HTTP version headers and SHA-256 hash.
- Processing is a separate, repeatable step: the same raw inputs always produce the same published numbers.
- Nothing is silently dropped. Every excluded or corrected record is logged with the rule that excluded it, and those logs are browsable below and in each chart.
- Automated checks halt publishing when a refresh looks wrong (for example, a total falling or many rows disappearing) until a person reviews it.
- Manual corrections (such as a party label) are listed in the methodology of every chart they affect.
Sources
FEC candidate master file (cn)
Federal Election Commission
Every registered federal candidate: name, party, office, state/district, incumbent status, principal campaign committee.
- fec-bulk:2026:cn · published Mon, 19 Oct 2026 05:41:58 GMT · retrieved
- fec-bulk:2014:cn · published Mon, 31 Dec 2018 05:23:49 GMT · retrieved
- fec-bulk:2018:cn · published Sat, 31 Dec 2022 07:18:14 GMT · retrieved
- fec-bulk:2022:cn · published Wed, 14 Oct 2026 05:38:57 GMT · retrieved
FEC candidate–committee linkage file (ccl)
Federal Election Commission
Which committees are authorized by which candidates.
- fec-bulk:2026:ccl · published Mon, 19 Oct 2026 05:42:07 GMT · retrieved
FEC all-candidates summary file (weball)
Federal Election Commission
Two-year cycle totals for every candidate as of their latest filed report: receipts, disbursements, cash on hand, debts, coverage end date.
- fec-bulk:2026:weball · published Mon, 19 Oct 2026 05:41:46 GMT · retrieved
- fec-bulk:2014:weball · published Tue, 31 Dec 2024 07:06:21 GMT · retrieved
- fec-bulk:2018:weball · published Wed, 14 Oct 2026 05:38:43 GMT · retrieved
- fec-bulk:2022:weball · published Wed, 14 Oct 2026 05:38:45 GMT · retrieved
FEC independent expenditures file
Federal Election Commission
Outside spending supporting or opposing a federal candidate, from 24/48-hour reports and periodic Schedule E filings, with amendments.
- fec-bulk:2026:ie · published Mon, 19 Oct 2026 10:13:29 GMT · retrieved
- fec-bulk:2014:ie · published Wed, 14 Oct 2026 10:13:44 GMT · retrieved
- fec-bulk:2018:ie · published Wed, 14 Oct 2026 10:13:49 GMT · retrieved
- fec-bulk:2022:ie · published Wed, 14 Oct 2026 10:13:53 GMT · retrieved
FEC itemized contributions (indiv: individuals; oth: committees and organizations)
Federal Election Commission
Every itemized contribution to a federal committee: contributor name, city, ZIP, employer, occupation, amount, date, recipient committee and scanned-filing image number.
- fec-bulk:2026:indiv · published Sun, 18 Oct 2026 16:22:02 GMT · retrieved
FEC committee master (cm) and PAC & party summary (webk)
Federal Election Commission
Every registered committee's type, party, connected organization and sponsoring candidate, plus PAC and party totals (receipts, disbursements, independent expenditures).
- fec-bulk:2026:webk · published Mon, 19 Oct 2026 05:41:54 GMT · retrieved
OpenFEC: itemized individual contributions by state, per candidate
Federal Election Commission (OpenFEC API)
Aggregated itemized (>$200) individual contributions to a candidate's authorized committees, grouped by contributor state. Unitemized small-dollar gifts have no state and are not included.
- 98 API response(s) cached, retrieved 2026-10-15 – 2026-10-19 · retrieved
OpenFEC: committee financial reports
Federal Election Commission (OpenFEC API)
Per-report receipts, disbursements and cash on hand for each principal campaign committee (most recent amendment only).
- 98 API response(s) cached, retrieved 2026-10-15 – 2026-10-19 · retrieved
VoteHub polling API
VoteHub
Individual public polls: pollster, field dates, sample size, population, sponsor, toplines, and a link to the original release.
- 5 API response(s) cached, retrieved 2026-10-19 – 2026-10-19 · retrieved
Donald Trump job-approval polls (Wikipedia)
Wikipedia contributors
Monthly tables of national job-approval polls, each linked to its release; merged with VoteHub's, with duplicates removed.
- 11 API response(s) cached, retrieved 2026-10-15 – 2026-10-19 · retrieved
Other aggregators' approval and generic-ballot averages (Wikipedia)
Wikipedia contributors, tabulating Decision Desk HQ, FiftyPlusOne, NBC News, RealClearPolitics, Silver Bulletin and others
Each aggregator's current national average, shown for comparison; the generic-ballot median stands in for this site's average only when too few pollsters have polled recently.
- national-aggregates (wikipedia:Opinion polling on the second Trump presidency; 2026 United States House of Representatives elections) · retrieved
Cook Partisan Voting Index (via Wikipedia)
The Cook Political Report with Amy Walter; tabulated on Wikipedia
How much more Democratic or Republican each state/district voted than the nation in recent presidential elections (vote-share points).
- pvi-state (wikipedia:Cook_Partisan_Voting_Index) · retrieved
- pvi-district (wikipedia:Cook_Partisan_Voting_Index) · retrieved
2026 U.S. Senate general-election candidates (Wikipedia)
Wikipedia contributors
Who is on each state's November ballot. Senate contenders are chosen only from this list, so a primary loser, a retiring incumbent or a minor-party candidate with more money never stands in for a nominee. Pulled once after the primaries.
- senate-nominees (wikipedia:2026_United_States_Senate_elections) · retrieved
U.S. House elections 2014, 2018, 2022: national popular vote (Wikipedia infoboxes)
Wikipedia contributors, citing the Clerk of the U.S. House of Representatives
Each party's share of the national House vote in past midterms, used as where the generic ballot ended up.
- house-popular-vote (wikipedia:United_States_House_of_Representatives_elections) · retrieved
2025 New Jersey and Virginia gubernatorial elections: certified results (Wikipedia infoboxes)
Wikipedia contributors, citing the New Jersey Division of Elections and Virginia Department of Elections
Final results of finished races, compared with this site's election-eve polling average as a check on polling error.
- calibration-results (wikipedia:election infoboxes) · retrieved
How Accurate Have Senate Polls Been, And What Could That Mean For November?
FiveThirtyEight (ABC News)
Senate polls in the final 21 days before an election have missed the final margin by 5.2 points on average since 1998 (weighted average absolute error). Sets the size of the simulated polling error.
Not yet retrieved.
Go to source ↗2026 gubernatorial candidates (Wikipedia)
Wikipedia contributors
Party affiliation for governor candidates, who do not file with the FEC.
- governor-candidates (wikipedia:2026_United_States_gubernatorial_elections) · retrieved
Citizen Voting Age Population special tabulation, ACS 2020–2024
U.S. Census Bureau
Estimated U.S. citizens aged 18+ by state and congressional district (119th Congress). Used for per-eligible-voter figures.
- census:cvap · published Fri, 30 Jan 2026 11:16:08 GMT · retrieved
Consumer Price Index for All Urban Consumers (CPI-U), series CUUR0000SA0
U.S. Bureau of Labor Statistics
Annual averages used to express past cycles in current dollars. The current year uses the average of months published so far.
- cpi (bls:CUUR0000SA0) · retrieved
2022 General Election Turnout Rates (v1.1)
Michael McDonald, U.S. Elections Project / University of Florida Election Lab
Ballots counted in the 2022 midterm as a share of each state's voting-eligible population. Used to estimate how many people will vote in each 2026 race.
- turnout-2022 (https://election.lab.ufl.edu/data-downloads/turnoutdata/Turnout_2022G_v1.1.csv) · retrieved
U.S. Senate statewide 1976–2024 and U.S. President 1976–2024
MIT Election Data and Science Lab (Harvard Dataverse)
Certified general-election vote counts for every candidate, by state. Used for actual Senate results and each state's previous presidential margin.
- senate-results (https://dataverse.harvard.edu/api/access/datafile/13887039?format=original) · retrieved
- president-results (https://dataverse.harvard.edu/api/access/datafile/13887042) · retrieved
Voting and Registration in the Election of November 2022, Table 4a
U.S. Census Bureau, Current Population Survey Voting and Registration Supplement
Share of citizens 18+ in each state who reported being registered (69.1% nationally) and who reported voting (52.2%) in 2022. The gap between the two sets how far turnout can rise before the electorate looks like all registered voters.
- cps-registration-2022 (https://www2.census.gov/programs-surveys/cps/tables/p20/586/vote04a_2022.xlsx) · retrieved
Party Division, 119th Congress
United States Senate
Seats held by each party going into the 2026 election (independents counted with the party they caucus with). Used to add the seats not on the ballot to the projected Senate.
Not yet retrieved.
Go to source ↗Field-experiment estimates of cost per additional vote
Green & Gerber, Get Out the Vote (Brookings); Nickerson (2005); Kalla & Broockman (2018)
Randomized experiments put mobilization costs at roughly $19–$31 per additional vote for door-to-door canvassing and higher for phones and mail (figures as reported from earlier editions). Persuasion in general elections is far harder: Kalla & Broockman's meta-analysis finds effects near zero.
Not yet retrieved.
Go to source ↗Excluded records
Records removed from the raw sources, by rule. Open any chart's Sources & methods → Exclusions tab to see the individual records and their original filings.