2 candidates are tracked for Adams County Commissioner District 4 on the November 3, 2026 ballot: Karen DeAguero and Joseph P. Domenico. Candidate information follows official Adams County election filings; verify with the official election office linked below.
District 4 is an open seat: sitting Commissioner Steve O'Dorisio, per the county's official commissioners page, did not appear as a candidate in either party's June 30, 2026 primary, per the certified canvass. Democrat Karen DeAguero won a contested primary over Tyler Quick, 29,805 votes (50.59%) to 29,111 (49.41%). Republican Joseph P. Domenico was unopposed in his primary (25,758 votes, 100%). Both advance to the November 3, 2026 general election.
County commissioner. The county board is the county's legislative and, in most states, executive body. Commissioners adopt the county budget and property tax rate, oversee roads, the jail, public health, planning and zoning in unincorporated areas, and appoint or confirm department heads. In counties with an elected county executive or judge, the board's role is mainly the budget and ordinances.
Colorado › Adams County › Adams County Commissioner District 4
Democratic
Per the campaign site.
DeAguero is an engineer and non-profit founder, per the Adams County Democratic Party. Her campaign site says she brings technical expertise and a data-driven approach to county government, per her campaign site.
Republican
Domenico was previously the 2022 Republican nominee for this same seat and ran unopposed in the 2026 Republican primary, per Denver Gazette. No campaign website was found as of September 8, 2026.
Who is running for Adams County Commissioner District 4 in 2026?
2 candidates are tracked for Adams County Commissioner District 4 on the November 3, 2026 ballot: Karen DeAguero and Joseph P. Domenico. Candidate information follows official Adams County election filings; verify with the official election office linked below.
When is the Adams County Commissioner District 4 election in Colorado?
Election Day is Tuesday, November 3, 2026. Registration deadlines, early voting dates and mail ballot rules for Colorado are on the Colorado election hub at theballotbrief.com.
How do I see my exact Adams County ballot?
Enter your ZIP code in the lookup at theballotbrief.com for the statewide and congressional races, or a full street address to add the county, city and district contests for that location.
Candidate roster from official Adams County and state election office filings, last verified September 25, 2026. Bios and priorities carry their attribution inline.
Cross-check with the official Colorado election office, or see the full Adams County sample ballot and your exact ballot by address.
20 tracked races in Adams County, Colorado. Landed here from another county's search? Look up your own ballot below.