Colorado

Registration is reported across eleven party codes — Unaffiliated, Democratic, Republican, Libertarian, No Labels, American Constitution, Green, Approval Voting, Center, Unity and Forward. Unaffiliated holds 2,016,174 of 3,986,025 active registrations, an outright majority and more than both major parties together. A schema with a two-party column and an other bucket loses the plurality of the electorate, and any model that treats primary eligibility as a function of party enrolment is wrong for half the state.

Unaffiliated electors are mailed primary ballots, but a minor party may prohibit them from voting in its primary by notifying the Secretary of State not less than 75 days before the primary — April 16 for the June 30 election. So whether an unaffiliated voter can participate in a given party's primary is a per-party, per-cycle decision with its own filing deadline, and it can change between cycles without any change in law. The resulting electorates are not comparable across parties or across years.

The Secretary of State's 2024 general precinct workbook carries Active, Inactive and Total columns and computes its turnout against Total — 3,239,261 over 4,579,953, or 70.73%, where the same ballots against active registrations give 79.56%. The 2026 primary feed reports a denominator of 4,025,423, which tracks the active count rather than the total. Two official surfaces, two answers, 8.83 points apart. And registration carries a third category, pre-registered sixteen and seventeen year olds — 114,697 of them — who sit inside the grand total and cannot vote.

Colorado runs all-mail elections, and the clerk must send a mail ballot packet to each active eligible elector — October 9 for the 2026 general. Inactive electors, 582,596 of them, are not sent one. So inactive is not a bookkeeping flag here as it is in a poll-site state; it is the difference between receiving a ballot and not. A pipeline that folds inactive into a single registered-voter figure both inflates the denominator and hides which voters the state actually reached.

Three Regent of the University of Colorado seats and three State Board of Education seats appeared on the 2026 primary ballot apportioned to congressional districts 1, 2, 3, 6 and 7. These are state offices whose constituencies are federal districts, so their boundaries change at every congressional redistricting, and a seat's electorate can be redrawn by a process that has nothing to do with the office. Anything treating a state office's district as a state-defined geography will drift out of date silently.

Of 3,715 local governments the Census counts in Colorado, 3,201 are special districts and only 272 are municipalities. Metropolitan, water, sanitation, fire, library and park districts overlap each other and cross municipal lines freely, each with its own elected board and its own election. The word district therefore carries no implication about scale, function or containment, and a harvest that models municipalities as the local layer captures under a tenth of the state's governments.

The state's certified 2026 primary abstract is published as a scanned PDF — jbig2 stencils, no embedded fonts, zero extractable text — so the authoritative record is the one artifact that cannot be parsed, and every machine-readable figure comes from a feed that is not the certified document. Separately, the 2024 precinct workbook carries a 400-character explanation of a Montezuma County ballot error, in which voters were moved to a different precinct to receive a missing school district question, as a row in the data. A naive parser reads it as a county.

Colorado administers elections through 64 counties, and both the state's registration file and its 2026 primary feed report 64. The Census of Governments counts 62 county governments, because Denver and Broomfield are consolidated city-and-counties and are classified as municipal. So a harvest reconciled against Census unit counts is short two, and the two missing ones are among the largest — Denver alone holds 301 precincts and 459,250 active voters.