The words, before they are used.
The terms used across this site, defined in one place. Each is also explained where it first appears.
- Roll call
- A recorded vote, where each member’s individual position is written down. Most business in Congress passes by voice vote with no record of who said what; a roll call is the subset that leaves evidence. This site holds only roll calls, which is why a member’s “votes cast” is far short of everything their chamber decided.
- Party unity
- How often a member voted with the majority of their own party, counted over the roll calls where the two parties’ majorities disagreed. A high number means they rarely broke ranks. It is not a measure of loyalty, effectiveness or agreement with any voter: it counts one thing.
- DW-NOMINATE
- A statistical estimate of where a legislator sits relative to everyone else in the same chamber, computed from who votes with whom — never from anyone’s reading of the bills. Published by Voteview, the method is the standard in political science. The number has no units and no meaning outside its own chamber: it says a member votes more like this group than that one, and nothing about whether they were right.
- Representation gap
- The distance between how a member votes and what their seat’s own presidential result predicts a member from that seat would vote. It is a distance, not a verdict: a member may be further from their district’s presidential lean than average for reasons no statistic can see.
- PACPolitical action committee
- A committee registered with the Federal Election Commission that raises money and gives it to candidates, within legal limits. Corporations and unions cannot give to a federal candidate directly; a PAC connected to one can. The FEC files a type for essentially every committee, and a connected organisation for about one in five — 3,940 of the 20,531 here name a sponsor, and a further 8,921 file the word NONE — the committee stated it has no sponsor. The funding pages show these filings as filed.
- Super PAC
- A committee that may raise and spend without limit, on the condition that it never coordinates with a campaign. It cannot give a candidate money; it spends on its own advertising instead. Its own funders are filed with the FEC too, which is why a committee’s largest backer is shown beside its name.
- Independent expenditure
- Money spent to support or oppose a named candidate by someone who is not their campaign and is not coordinating with it. The spender files it with the FEC and ticks whether it was for or against — that ticked flag, not an inference here, is what puts money on one side of a race on this site.
- The proportion of a campaign’s receipts, in a single cycle, that came from people giving under $200, the threshold below which the FEC does not require a donor to be itemised. It is reported by the campaign in its own summary filing. A campaign only files one for a cycle it is a candidate in, so for a senator not on the ballot the figure is from whichever cycle they last ran, and the card says which.
- Corporate/Labor balance
- Of the PAC money a member received that the FEC typed as either corporate or labor, which side it leaned to, over the 2026 cycle. Committees the FEC typed as neither are not counted, so the figure describes a slice of the money rather than all of it — which is why the two dollar totals it is computed from are printed beside it. It covers two years, not a career: a member’s balance can invert between cycles.
- Percentile
- A position in a ranked group, not a score. “More conservative than 15% of Republicans” means exactly that: rank the Senate’s Republicans by their ideology estimate and 15% of them sit to this member’s left. It says nothing about the size of the gaps between them.
- Prediction-market price
- What a trader is currently paying for a contract that pays out if an outcome happens. This site publishes prices as prices. A price is not a forecast, and never this site’s probability — see what this refuses to do.
- Certified result
- The official count published by the state that ran the election. Certified counts take primacy over every other number about the same contest on this site, including any market price or poll average beside them.
See them in use.
Every one of these words appears on a seat’s page with the figure it describes and the document behind it.
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