The Republican presidential primary race is revolving entirely around the Broadmoor World Arena in Colorado Springs, Colo., on Saturday.

That's where Colorado Republicans are meeting to elect 13 statewide delegates to this summer's Republican National Convention.

In a contest that takes 1,237 delegates to win the nomination, 13 – or even the full 37 Colorado will send to Cleveland — may seem like a minuscule total.

But with the odds of a historic contested convention growing larger and larger — especially after Ted Cruz's big win in Wisconsin this week — every delegate counts.

Colorado has already been good to Cruz. Before Saturday's statewide delegate vote, Republicans in each of Colorado's congressional districts voted on three delegates. "Here in Colorado, ya'll have had seven elections in the past week," Cruz told the arena during an appearance here. "Collectively, those seven elections have elected 21 delegates, and of those 21 delegates, together we won all 21."

If Cruz sweeps all 13 statewide delegates — an outcome many Cruz backers in Colorado see as possible — he would walk out of the state with more delegates than he picked up in Tuesday's Wisconsin primary.

The Cruz campaign's strength has a lot to do with a finely honed ground game and volunteer organization. "Dozens of volunteers have been working since December" in Colorado, said Congressman Ken Buck, who's chairing Cruz's Colorado campaign.

On Saturday morning, Cruz volunteers wearing bright orange shirts swept through the arena, handing out glossy sheets listing the campaign's preferred delegate candidates.

"We put 15 delegate [candidates] forward," said Buck, who is running himself. "We looked at people that had run and won in the past. We looked at people who had been supporting Cruz for a long time. We looked at elected officials who knew how to run campaigns."

The number of Donald Trump volunteers distributing candidate slates was much, much smaller. And the Trump slate had several errors: Many of the candidates it listed didn't match up to their assigned numbers on the ballot. That matters, as there are nearly 600 people running.

Others on the Trump slate are listed on the ballot as "uncommitted," rather than supporting Trump.

One of Trump's volunteers, Tony Polisi, said he didn't expect Trump to win any delegates on Saturday. "Most everybody here is for Cruz. They're not voting Trump," he said.

The slate of Trump candidates Polisi was handing out had six candidate names listed. Polisi told people to only vote for those candidates so that "we can concentrate the vote."

When asked whether that audible play was something the Trump campaign had instructed him to do, Polisi said, "Nope. This is something Tony Polisi decided on."

"I'm a doer," he added. "Trump's a doer. We're going to get things done."

Front-runner Trump won't have a chance to clinch the nomination and stave off a Cleveland floor fight until the very last day of the GOP primary process, June 7. In recent days, several reports have emerged indicating that the Trump campaign has run into roadblocks.

According to Politico, top Trump advisers are fighting for power as the campaign struggles to shift from a rally and media-centered populist appeal, to the insider political scramble to secure as many delegates as possible.

The Trump campaign organization has always been relatively small, and in Colorado those organizing shortfalls have been apparent. All 21 delegates elected by Colorado's congressional districts ahead of Saturday's state convention say they'll back Cruz in Cleveland.

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