DENVER (CBS4) – With Colorado’s first primary in two decades less than three weeks away, presidential candidates are lining up to campaign in the Centennial State. A Bernie Sanders rally on Sunday night at the Colorado Convention Center drew thousands of Democratic supporters.

(credit: JASON CONNOLLY/AFP via Getty Images)

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In 2016, Sanders came out in top in Colorado’s Democratic caucuses, but caucuses tend to draw idealogues. The primary in Colorado allows unaffiliated voters to cast ballots, and Sanders’ populist message may not play as well with them.

However, the large showing of support on Sunday night is perhaps a sign that there might be enough Colorado progressives for Sanders to win the primary, CBS4 Political Specialist Shaun Boyd reports.

Michael Bloomberg in a campaign appearance in Aurora in December

Michael Bloomberg in a campaign appearance in Aurora in December (credit: CBS)

Sanders says he wants to bring an end to a system in which billionaires can buy elections, and he referred to rival Michael Bloomberg in his speech. Bloomberg, the billionaire and former New York mayor, has focused his campaign on Colorado and other Super Tuesday states, spending millions of dollars. Sanders says Bloomberg was bored and decided he wanted to be president.

Bernie Sanders greets supporters after a campaign rally in Denver on Sunday night. (credit: JASON CONNOLLY/AFP via Getty Images)

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Sanders is seeking to keep his momentum after strong showings in Iowa and New Hampshire. He also slammed what he called the corporate, media, GOP and Democratic establishments for trying to stand in his way.

“With your help, we are going to win here in Colorado, we’re going to win the Democratic nomination and we are going to defeat the most dangerous president in modern history,” Sanders said.

Officials say about 11,000 people attended the rally for Sanders.

PHOTO GALLERY: Bernie Sanders Campaign Rally In Denver

President Donald Trump and Democratic candidates Joe Biden, Pete Buttigieg and Elizabeth Warren are also scheduled to make campaign appearances in Colorado this week.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)