County clerks finished posting unofficial results in Colorado’s primary election on Friday, drawing a line under a series of nominating contests that witnessed upsets, surprises and outright shockers by the time the votes were tallied.

While the outcome changed in only one major, top-ticket race after the initial returns were reported on June 30, several candidates declared winners on election night saw their leads swell as clerks added same-day and late-arriving votes to the totals.

Another statewide candidate, who appeared to cruise to renomination, easily securing a win hours after polls closed, turned out to have won by a closer-than-comfortable margin after all the ballots had been counted.

The top-ticket primary race that traded leaders after election night was also the one that took the longest to be called, with ministry leader Victor Marx’s narrow win in the Republican gubernatorial contest remaining likely — but still too close to call — until Thursday afternoon, nearly nine days after ballots were due.

State Sen. Barb Kirkmeyer, Marx’s chief rival in the three-way race, jumped out to an early lead on primary night, but by the following afternoon, Marx had overtaken her with the roughly 2,000-vote lead that he would maintain for the duration, enough for his historically slim 0.5 percentage point lead in the final tally. State Rep. Scott Bottoms finished a distant third.

Seeking his second term, U.S. Sen. John Hickenlooper locked in the Democratic nomination early on primary night, leading his challenger, state Sen. Julie Gonzales, by a solid 14 percentage points when the Associated Press declared he had won.

However, as more ballots trickled in over the next eight days — including a swell of votes cast on election day in Denver — Hickenlooper’s lead dwindled to just under 6 percentage points, suggesting that the former two-term governor’s position with his party’s electorate was more precarious than had been assumed.

Primary voter turnout jumps

State voters turned out this year in markedly higher numbers than they did two years earlier in the 2024 primary, which featured just a single statewide primary, to decide the Democratic nominee for the at-large seat on the University of Colorado Board of Regents.

In contrast, the 2026 primary ballot had plenty of contested races for Democrats and Republicans alike, in part owing to every one of Colorado’s state-level executive offices being open this year, for the first time in memory. That’s because the Democrats who occupy those seats — Gov. Jared Polis, Secretary of State Jena Griswold, Attorney General Phil Weiser and State Treasurer Dave Young — face term limits after the parties’ nominees swept into office in 2018 and each cruised to reelection in 2022.

Total turnout in the 2026 primary stood at nearly 36% of active registered voters as of Friday afternoon, the Colorado Secretary of State’s Office reported — up substantially from the 26% turnout logged in the 2024 primary.

In raw numbers, that means 1,444,265 of the state’s 4,024,717 active registered voters returned ballots this year, compared to 987,867 primary ballots returned out of 3,801,641 active registered voters in 2024.

Broken down by affiliation and ballot choice, far more voters cast ballots in the Democratic primary than voted in the GOP primary, reflecting both party members who voted and the unaffiliated voters who decided, by a wide margin, to participate in the Democratic primary.

Under Colorado’s semi-open primary system, unaffiliated voters — who make up just over 50% of the state’s registered electorate — receive ballots from both major parties and can choose which to return.

Unusually this year, unaffiliated voters could also cast a ballot in the Unity Party’s primary, though only about 100 did. The Libertarian primary was closed, meaning only registered members of the minor political party could participate.

Unaffiliateds flock to Dem primary

According to preliminary figures released Thursday by the Secretary of State’s Office, clerks received nearly 880,000 Democratic primary ballots and just under 525,000 Republican ballots, along with just over 3,700 Libertarian ballots and just shy of 300 Unity Party ballots. Those figures don’t include almost 70,000 unaffiliated ballots that were still in process and hadn’t yet been allocated to either party’s pile.

Again using the preliminary totals for comparison’s sake, that works out to just over 490,000 ballots cast by registered Democrats and just short of 375,000 cast by registered Republicans. In addition, close to three times as many unaffiliated voters chose to cast ballots in the Democratic primary as voted in the Republican one, according to the Secretary of State’s Office, with 72% helping choose Democratic nominees and just 28% checking boxes to pick the GOP’s ticket.

Crowded ballots abound

This year’s statewide ballot was chock full of choices, with the Democratic and Republican gubernatorial nominations up for grabs, a spirited Democratic primary for the U.S. Senate, and attorney general primaries in both parties. Additionally, the Democrats and Libertarians chose secretary of state nominees, and the tiny Unity Party held a contest to name its candidate for governor.

Five of the state’s eight congressional districts also saw contested primaries, though both parties only had the chance to weigh in on their nominees in the Western Slope-based 3rd Congressional District.

Democratic U.S. Rep. Diana DeGette, the state’s longest-serving member of Congress, became only the second House incumbent to lose a primary in Colorado in the last 50 years when she lost her bid for a 16th term to 29-year-old Melat Kiros, a doctoral student and former attorney making her first run for office. CU Regent Wanda James trailed in third place.

Democratic voters designated challengers to three Republican incumbents — picking Dwayne Romero to take on U.S. Rep. Jeff Hurd in the 3rd CD, tapping Jessica Killin to face U.S. Rep. Jeff Crank in the 5th CD, and handing the nomination to state Rep. Manny Rutinel to go up against U.S. Rep. Gabe Evans in the swingy 8th CD.

On the Republican side, Hurd easily turned back a challenge for renomination from former state Rep. Ron Hanks in the 3rd CD, while Kelley Anne Dennison won the primary in the 2nd CD and will run against Democratic U.S. Rep. Joe Neguse.

Margins swell in some races

Votes reported after primary night pushed several candidates into more commanding leads than they’d enjoyed when their races were called.

Weiser, who won the Democratic gubernatorial nomination over U.S. Sen. Michael Bennet, led the race’s early frontrunner by 10 percentage points at 8 p.m. on election night when the AP called the race, but his lead had stretched to nearly 14 percentage points by the time clerks posted final results.

Likewise, Kiros had pulled into a roughly 6 percentage point lead over DeGette by 10 p.m. on June 30, when the AP declared she had upset the incumbent, but by the final tally nine days later, Kiros saw her winning margin climb to more than 13 percentage points.

Rutinel’s lead over former state Rep. Shannon Bird didn’t increase by quite as much as the count continued, but after being declared the Democratic nominee in the 8th CD while leading Bird by a 24 percentage point margin on election night, he’ll go down in the books as having won by 30 percentage points.