How Colorado Got Here

National context: Civil War soldiers vote away from home

The Civil War brings widespread military absentee voting. For the 1864 election, states allow soldiers to vote away from home, including at polling places in the field. Absentee voting does not always mean voting by mail; these arrangements vary by state.

Source: Library of Congress, “Voting in the Field”.

Military service does not erase voting residency

Colorado’s constitution protects a person’s voting residence during absence for military service. This residency protection does not itself establish a procedure for voting by mail.

Source: Colorado Constitution, Article VII, Section 4.

Citizens gain the initiative and referendum

Colorado voters approve a constitutional amendment allowing citizens to propose laws and constitutional amendments by petition for a public vote. Citizen initiatives become available in 1912.

This helps explain why Colorado ballots include policy choices alongside candidates. Measures can originate with citizens or be referred by the legislature. These measures add to ballot length and the reading voters need to do before making their choices.

Sources: Colorado General Assembly, history of ballot measures; Colorado Judicial Branch, ballot initiatives.

Colorado authorizes absentee voting by mail

A law approved March 18, 1915, permits absent electors to vote by mail. Colorado’s use of mailed absentee ballots thus predates statewide mail-ballot delivery by nearly a century.

Source: 1923 legislative index identifying the 1915 act.

Colorado voters approve motor-voter registration

Colorado voters approve Amendment 4, allowing eligible residents to register to vote when applying for a driver’s license. Colorado takes this step before Congress passes the federal “Motor Voter” law in 1993.

Sources: Colorado Secretary of State, 1984 Amendment 4; U.S. Department of Justice, federal motor-voter law.

Colorado enacts the Mail Ballot Election Act

Colorado lawmakers pass SB90-97, allowing local governments to choose mail-ballot elections for nonpartisan candidates and ballot issues, subject to state oversight. The law excludes elections involving partisan candidates and elections held alongside, or on the same day as, primary, general or congressional vacancy elections. Approved in 1990 and effective in 1991, it establishes an early framework for conducting entire elections by mail.

Source: SB90-97, 1990 Colorado Session Laws, Chapter 43, pp. 314–318.

Early voting and election coordination develop further

HB93-1255 refines the procedures for casting, receiving, counting and challenging early and absentee votes, and requires accessible early-voting polling places. It also clarifies county clerks’ responsibility for coordinated elections and helps voters cast ballots for multiple jurisdictions at one polling place. Approved June 6, 1993, the law takes effect July 1, 1993.

Sources: 1993 legislative digest, HB93-1255, pp. 56–58; original act, 1993 Colorado Session Laws, Chapter 258.

Federal NVRA expands voter registration

Congress enacts the National Voter Registration Act, often called “Motor Voter.” The federal law expands registration opportunities through motor vehicle agencies, mail applications and designated public agencies, while also establishing requirements for voter-list maintenance.

Sources: U.S. Department of Justice: National Voter Registration Act.

Early-voting framework expands

HB96-1061 separates existing early-voting provisions and requires every county clerk to provide an early-voting polling place. It takes effect July 1, 1996.

Sources: HB96-1061: 1996 legislative digest.

Donetta Davidson helps lead Colorado’s election reforms

Following the 2000 presidential election, Secretary of State Donetta Davidson established a task force to identify potential problems in Colorado’s election process and recommend legislative solutions.

That work helped inform HB02-1307, which expanded provisional voting to precinct polling places, improved information sharing for voter-registration records and required signature checks on absentee-ballot envelopes.

HAVA modernizes election administration

Following the 2000 presidential election, federal law brings new voting-system standards, accessibility requirements, provisional ballots, statewide registration-system requirements and the Election Assistance Commission.

Sources: U.S. Department of Justice: Help America Vote Act; Electionline: Colorado’s 2002 reforms.

Vote centers emerge

Larimer County uses vote centers in its 2003 coordinated election. SB04-153 establishes statewide authority for counties to use the model in 2004.

Permanent Mail-In Voting

SB07-234 establishes the Permanent Mail-In Voter framework. Eligible voters can choose permanent mail-in status so they continue receiving mail ballots without making a new request election after election.

Sources: SB07-234: 2007 legislative digest, pp. 61–62.

Mail-ballot primaries + risk-limiting audits

HB09-1015 authorizes mail-ballot primary elections. HB09-1335 also establishes the statutory requirement for risk-limiting audits, later implemented statewide in 2017.

Sources: HB09-1015: mail-ballot primaries; HB09-1335: risk-limiting audit requirement.

Federal MOVE Act strengthens voting for military and overseas citizens

Congress expands UOCAVA through the Military and Overseas Voter Empowerment Act. Among its major changes, states must provide electronic options for receiving registration and ballot materials and transmit validly requested absentee ballots to covered voters at least 45 days before federal elections when the request is received by that deadline. Most requirements take effect for the 2010 election cycle.

Sources: Justice Department: MOVE Act implementation; Justice Department: UOCAVA requirements.

Online voter registration

Colorado launches online voter registration, adding another way for eligible voters to maintain their registration.

Sources: Department of State: FY2014–15 strategic plan, online registration history.

Colorado helps launch ERIC

Under Secretary of State Scott Gessler, Colorado becomes one of seven founding states of the Electronic Registration Information Center (ERIC) in 2012. The bipartisan, multistate initiative uses registration and motor-vehicle data to help election officials identify outdated and potentially duplicate voter records.

Sources: ERIC: founding states and list-maintenance work.

Counties pilot a uniform voting system

Eight Colorado counties test equipment from four vendors during the November 2015 election. The Pilot Election Review Committee (PERC) examines the pilot experience and hears from vendors as Colorado evaluates options for a more uniform voting system.

Clear Ballot is piloted in Adams and Gilpin counties; Dominion in Denver and Mesa; ES&S in Jefferson and Teller; and Hart InterCivic in Douglas and Garfield. The trials bring practical experience from voters, election judges and county staff into the selection process.

Unaffiliated voters enter party primaries

Voters approve Propositions 107 and 108 in 2016. Implementation legislation follows in 2017, and unaffiliated voters begin participating in major-party primaries under the new model in 2018.

Sources: SB17-305: 2017 implementing legislation and rules; Secretary of State: 2018 unaffiliated-primary announcement.

Election infrastructure designated as critical infrastructure

On January 6, 2017, U.S. Department of Homeland Security Secretary Jeh Johnson designates election infrastructure as critical infrastructure during the Obama administration. The designation gives election officials priority access to federal security assistance and strengthens coordination and threat-information sharing.

For Colorado and other states, the designation supports security cooperation while election administration remains under state and local control. Participation in federal assistance is voluntary.

First statewide risk-limiting audit

Colorado becomes the first state to complete a statewide risk-limiting audit, using paper ballots to statistically test reported outcomes.

Automatic voter registration develops

Colorado introduces front-end automatic voter registration at the DMV in 2017. Legislation expands the system in 2019, and back-end automatic registration begins in 2020.

Sources: Grimmer and Rodden: Colorado’s AVR stages, section 3; SB19-235: automatic registration expansion.

National attention for Colorado's security model

The Washington Post publishes “How Colorado became the safest state to cast a vote,” highlighting paper ballots, audits and election-security practices.

Read the Washington Post article →

CCCA proposes an election-integrity improvement agenda

In a June 29 letter to the Bipartisan Election Advisory Committee, CCCA recommends stronger signature-verification audits, review of voter-list maintenance, public access to ballot images and cast vote records at no cost with protections for voter anonymity, and modernized election funding.

Led by CCCA, this initiative brings together representatives from the Colorado Secretary of State’s office, national election experts and other stakeholders focused on improving Colorado elections.

Signature-audit enhancements and funding modernization have since been achieved. Work continues on other initiatives, and CCCA’s agenda has expanded to enhancements to the risk-limiting audit—improving its transparency, clarity and usefulness while preserving rigorous verification of reported election outcomes.

Sources: Read CCCA’s original June 29, 2021 recommendations (PDF).

Sources: Signature-verification audit requirements; Election funding modernization, SB23-276.

Signature-verification audit requirements are strengthened

Colorado adopts more detailed requirements for auditing signature-verification decisions in December 2025. The rules specify random sampling, timely review, trained auditors and corrective action, strengthening a safeguard CCCA called for in its 2021 recommendations.

Sources: December 22, 2025 rule adoption; Current Election Rule 7.7.8.