Colorado Republicans had a quick response to Sanders’ rally. Spokesman Kyle Kohli said the party is confident Sanders would struggle in the general election, citing his support for the universal health care measure that Colorado voters rejected soundly in 2016.

“Coloradans already made it loud and clear they have zero interest in Bernie Sanders’ government takeover of their health care,” Kohli said.

But in 2016, Sanders handily won the Colorado Democratic caucuses with 59 percent of the vote. Since then, Colorado has completely revamped how it chooses presidential nominees. Voters opted for a presidential primary and opened the process to unaffiliated voters.

Ballots have already gone out to Coloradans and votes will be counted on Super Tuesday, March 3.

Jane Sanders, the presidential contender’s wife, said the new system hasn’t changed how her husband will compete for Colorado. Their strategy still relies on driving unprecedented voter turnout, especially among young people who overwhelmingly support Sanders.

“Young people, who are the future of this country, appear the most progressive, the least bigoted, the most concerned about issues such as climate change, the cost of health care and education,” she said.

That was certainly the case for 22-year-old Rachel Boyle and 27-year-old Idan Erez. The pair camped outside the rally for as long as possible to avoid the noise inside. While both Boulder residents are passionate Bernie fans, they admitted it won’t be easy to drive people their age to the ballot box.

“I think there is a certain level of voters who you just aren’t going to reach, but I think Bernie is doing a lot more than other candidates,” Boyle said.

Erez agreed Sanders’ political strategy is risky, but she said it’s not just about making sure young people submit their ballots. She added “boomers” need to get over their fears of nominating a progressive candidate. Toward that end, she said she struck a deal with her parents: She’ll vote for any Democratic nominee come November if they vote for Sanders in the primary.

“Everyone should do this deal with their parents,” she said.

If that doesn’t work, she suggested emotional blackmail.

“Like ‘I’ll only love you if you vote for Bernie,’” she said. “You got to use what you’ve got.”

Hart Van Denburg/CPR News Bernie Sanders supporters cheer during his speech at a campaign rally at the Colorado Convention Center in Denver Sunday Feb. 16, 2020.

Honorah Lee, a 71-year-old from Lafayette, said at the rally that she proudly embraces the “boomer” label. She voted for Sanders in 2016, but worries his left-wing agenda and his recent heart attack could become liabilities in the general election.

“I’m frightened of his heart stents,” she said. “He’s seven years older than I am, and I’m no spring chicken. Does he have the juice to make it?”

Jane Sanders dismissed any concerns about her husband’s health. Since his heart attack last October, the candidate has released letters from three different doctors attesting to his fitness for office. Some critics have said the disclosure has fallen short of the medical documentation Sen. Sanders promised after his heart attack.

But if there was any real worry, Jane Sanders said she’d put an end to his campaign.

“I’d pull rank as a wife,” she said.