Colorado, home to one of the most chaotic state Republican parties in the nation, is one of six states or territories that decided not to hold a traditional caucus or primary to pick their presidential preference. Instead, the state party launched a months-long selection process.
With Friday's results, Cruz has a 21-to-0 delegate advantage over Trump and Ohio Gov. John Kasich. The senator earned 12 delegates — three each from the four congressional districts that held meetings Friday. He had won nine more delegates at three other district meetings held in the past week.
In Colorado, anyone seeking a delegate slot has the option of declaring a preference in advance or running as part of a slate of like-minded candidates. Pledged delegates who win must vote for their preferred candidate on the first ballot at the national convention. "Unpledged" delegates have until votes are cast in Cleveland to make a decision.
Most of the delegates Cruz has won in Colorado are formally pledged to him. Other winners officially ran as unpledged delegates but said they planned to vote for the senator in Cleveland.
While Trump continues to lead nationally and has won the most delegates in caucuses and primaries, he has repeatedly struggled in states that have more complex rules for selecting delegates. It happened again this week in Colorado.
A small band of Trump volunteers was trying to win last-minute votes at the convention on Saturday.
"Hey, hey Colorado! Trump supporters are here!" shouted Pamela Gentry, a real estate agent from Westcliffe, Colo., who started volunteering for Trump less than two months ago.
During congressional district meetings at at a nearby hotel on Friday, a Trump campaign booth and said they were supposed to be taking cues from a campaign staffer who had yet to appear. Trump senior campaign aide Stephen Miller later addressed one of the congressional district meetings.
But out in a hallway, white fliers asked convention-goers from the 5th Congressional District to vote for a Trump-backed slate that included Charles Prignano. But his last name was misspelled.
"It is the most disorganized campaign I've ever seen," he said.
A Colorado Springs resident with a long gray beard, Prignano used to steer gondolas full of tourists at the Venetian hotel in Las Vegas and once ran for Congress in Illinois. (He lost to future governor Rod Blagojevich.) He's been volunteering for Trump since last June.
"This is Cruz country," he lamented. But Prignano said he will keep supporting Trump because "he's not a full-time, professional politician. Number two, he's funding his own campaign and will not owe anything to lobbyists, special interests or other politicians. And number three, he's a successful businessman."
While Trump and Kasich sent surrogates to address the convention, Cruz is scheduled to speak Saturday and plans to spend less than three hours on the ground here before flying to Las Vegas to address the Republican Jewish Coalition. His appearance caps almost a year's worth of preparation by volunteers tapped by his campaign to lead a grass-roots recruitment and turnout effort. As part of the process, the campaign has recruited like-minded Republicans who have run for delegate positions in the past.
“Those are really the best indications of someone’s success in the future: Was there success four years ago or eight years ago,” said Rep. Ken Buck (R-Colo.), Cruz's state chairman. "There are some regulars who like going to the national convention and spend the time and money."
"If we lose a seat to someone who is unpledged, we will do our best to talk to that person about the advantages of voting for Ted Cruz," Buck added. "But my job is to make sure that doesn’t need to happen."
While Buck signed on with Cruz in December, the senator has been relying on volunteers such as Regina Thompson for far longer. Thompson, a longtime Colorado conservative activist, first met Cruz in 2011 just days after the Texan launched his upstart U.S. Senate campaign when he visited Colorado to address a retreat of conservative activists.
"By the time he was finished speaking, I had an internal sense that at some point in my life I would be supporting him for president," Thompson recalled. "I didn’t look at the calendar to see when it would be, but I said to myself, 'Watch, pay attention, he's going to be running.'"
Eager to help his campaign, Thompson met with Cruz campaign manager Jeff Roe at the Conservative Political Action Conference last year in Washington. With the campaign’s blessing, she began calling and emailing potential Cruz supporters in August.
"Out here, the only thing that you can do effectively here is not door-to-door campaigning, it’s driving people to attend caucuses," she said. "So what we started doing in August was finding those people around the state that would take on the task of making phone calls and driving people in their own communities to caucuses. It was a slow build-up, but it was building up a list of people who would make one-on-one contact to caucus."
More than 600 people signed up to run for the 13 statewide delegate slots — a process that could take hours given that each contender is scheduled to get just 10 seconds to address the crowd.
The state convention on Saturday will also help winnow the field of GOP candidates to challenge Sen. Michael F. Bennet (D-Colo.), an incumbent once considered among the most vulnerable who now faces less of a challenge if the party picks a lesser-known opponent. More than a dozen people are running to take on Bennet.
The Colorado Democratic Party said its Republican counterparts "muffled the voices of its voters" by scrapping its traditional presidential caucus.
"And though Ted Cruz will be the only Republican presidential candidate speaking at the Convention, let us also not forget that every single Republican running for president would take Colorado and America backwards," Colorado Democratic Party Chairman Rick Palacio said in a statement.