Colorado is gearing up to hold the state's first presidential primary in 20 years, and it falls on what political junkies call “Super Tuesday” — when the largest number of states and territories hold a presidential primary or caucus.

This year, it's March 3. Steve Hurlbert, spokesman for the Colorado Secretary of State's Office, said there's “no question” that Colorado holding its contest on that date will give the state a bigger spotlight in the primary season.

“Where we fall on the calendar is really important,” said Hurlbert, whose office oversees elections. “Also, the nature of what Colorado is: We're definitely a purple state and (one) that both parties see as up for grabs.”

Here are some important things to know before the primary elections, which will choose parties' nominees to compete in the November general election. Ballots were to be mailed out for the March primary the week of Feb. 10.

Back in vogue

Colorado's last presidential primary happened in 2000 — since then, presidential nominees were voted on at caucuses, which are overseen by political parties.

In primary elections, voters submit ballots in favor of their chosen candidate. A caucus is a system of local gatherings where voters decide which candidate to support — engaging in discussions at places such as high-school gyms — and select delegates that will ultimately cast votes at conventions to nominate candidates.

Hurlbert, referencing the recent news of a chaotic Iowa caucus marred by technological issues, argued the primary system has advantages.

“A primary system is run by the state election officials and not through a political party,” Hurlbert said. “That's the key thing — they're done by people who do this for a living and are some of the best at it in the country.”

Unaffiliateds can participate

In 2016, Colorado voters passed two initiatives, Propositions 107 and 108, which established a presidential primary system and allowed unaffiliated voters to participate in primary elections.

In the typical caucus — and some other states' primaries — voters are limited to the contest of the party with which they are affiliated.

Colorado's unaffiliated voters — those not registered to a political party — will receive both parties' ballots in the mail.

They can only vote and return one ballot, though — if they return both, neither will be counted, Hurlbert noted.

Unaffiliated voters who vote in a party's primary will remain unaffiliated. However, the primary they in which vote — but not who they voted for — will be a public record.

If there is a minor party contest — for parties other than Democrats and Republicans — those affiliated with that minor party can vote for those candidates.

17-year-olds good to go

An interesting aspect of Colorado's elections this year, Hurlbert said, is that it's the first year that 17-year-olds who turn 18 by the November election will be able to vote in Colorado’s two primaries (the one for presidential candidates and other in June for more local races).

Voter service and polling centers will be open for the March 3 primary starting Feb. 24. The state also allows same-day registration, so if voters haven't registered by March 3, they can register and vote on that day.

Two primaries and a caucus

On June 30, the state will hold this year's other primary election, which selects candidates for offices such as U.S. Senate, U.S. House, state Senate and House, and other regional or local races such as for district attorneys and University of Colorado regents.

There will be an indication of front-runners in those races before June, though: the caucus, which takes place March 7. Parties will still hold local caucus gatherings to gauge support before the June primary.

The presidential race will not have a caucus, though — only the March 3 primary.

Long list of candidates

The Democrats on the presidential primary ballot are (including some who have dropped out of the race): Cory Booker, Pete Buttigieg, Tulsi Gabbard, Bernie Sanders, Elizabeth Warren, Amy Klobuchar, Roque "Rocky" De La Fuente III, Michael Bennet, Marianne Williamson, Deval Patrick, Michael Bloomberg, Robby Wells, Andrew Yang, Joe Biden, Tom Steyer, Rita Krichevsky and John Delaney.

Republicans on the presidential primary ballot are Matthew John Matern, Robert Ardini, Joe Walsh, Donald Trump, Bill Weld and Zoltan Istvan.