Inside the Colorado state Capitol Feb. 5, 2019.

Colorado’s Democrat-controlled legislature approved a bill Thursday to join a compact that wants to tie states’ Electoral College votes to the winner of the national popular vote.

With the final vote needed in the Colorado House, a 34-29 tally, SB 19-042 will head to the desk of Gov. Jared Polis. The Democrat has indicated he will sign it.

Just as quickly as the bill left the legislature, a challenge was filed in order to check it.

Mesa County Commissioner Rose Pugliese and Mayor Don Wilson of Monument, in El Paso County, petitioned the Secretary of State’s office to bring the bill before voters in 2020. Pugliese, a Republican, thinks state lawmakers shouldn’t give “away our Electoral College votes without actually consulting with the voters of Colorado.”

“I'll be honest with you, since the national popular vote bill had been introduced, I get stopped on the street almost every day by constituents who do not want New York and California to decide where Colorado's Electoral College votes go,” she said.

Mayor Wilson and I filed a petition with the Secretary of State to keep Colorado’s votes for President in Colorado. We do not support the National Popular Vote, which allows California and New York to decide Colorado’s votes for President. #mesacounty #politicomom #coloradansvote — Rose Pugliese (@MesaCountyRose) February 21, 2019

Colorado’s nine electoral votes are currently awarded to the Presidential candidate who wins the state’s election. In 2016, Hillary Clinton bested President Donald Trump in the Centennial State. She also won the popular vote nationally but fell short in the Electoral College.

Sen. Mike Foote, one of the bill’s sponsors, insists this isn’t a partisan response to the president. Rather, the Longmont Democrat said it upholds a democratic principle: one person, one vote. He previously told CPR News that if you don’t live in a battleground state, “then your vote doesn’t count nearly as much.”

Great to see the National Popular Vote pass through the House today! Onto the @GovofCO. #coleg #copolitics pic.twitter.com/qpiXXbIXcO — Mike Foote (@SenMikeFoote) February 21, 2019

Like Pugliese, Democratic Rep. Emily Sirota, a bill co-sponsor, cited her constituents as her motivation.

"I hear time and again that my vote doesn't count," Sirota said. "That's the intention of this bill — to help people believe their vote matters."

State law allows a petition to put a new bill before a statewide referendum to ask voters if it should be repealed before it goes into effect. It is rarely used. Once the governor signs the bill, the Secretary of State will then review the format. From there, Pugliese said they will set up a committee, "so that we can raise money to educate voters. And then obviously we'd have to circulate petitions to actually get it on the ballot."

Even with Polis’ signature on the dotted line the change won’t be immediate.

It’s all dependent on the National Popular Vote compact and Colorado would only make the change if enough states sign on and commit their electors to the 270 needed to win the presidency. So far, 11 states and the District of Columbia have joined — a total of 172 electoral votes. The vast majority of those are from California.

Colorado is poised to become the 12th state. A national popular vote bill passed New Mexico’s House passed their bill in early February and will move to the state Senate.

There’s a broader question as to whether the compact is constitutional. Some observers insist Congress would have to approve the compact since it would overhaul national election procedures. Other scholars have argued that states can’t bind their electors to voters outside their boundaries.

Seth Masket, director of the Center on American Politics at the University of Denver, said those legal battles are a long way off. In the short term, he sees the compact as a way to refresh a familiar debate over the unique way the U.S. decides its president.

"It’s about saying the status quo is unacceptable," he said of compact supporters. "This might not be the best way of changing it, but it’s at least a way of forcing some change and forcing some discussion of it."

Hitching state electors to the popular vote isn’t a new idea in Colorado and has been turned back four times at the legislature. Republican lawmakers strongly opposed the proposal. The bill cleared both chambers this year without a single Republican vote on it.

Opponents say the initiative subverts an Electoral College that was designed by the Founding Fathers to ensure, in part, that smaller states aren't trampled over when it comes to choosing a president. They also insisted the matter should be put to the voters.

"Our founders feared the tyranny of the majority. In our Electoral College our smaller states still have a say," GOP Rep. Lori Saine warned before Thursday's vote. "This is an exercise of the tyranny of the majority."

While it appeared to be a partisan issue with legislators, Rose Pugliese doesn’t think it plays that way with everyday people across the state.

"I think voting is an issue that affects all Coloradans equally and obviously if it's on the ballot they'll get to weigh in on that."

CPR News’ Sam Brasch, Megan Verlee, Jim Hill and The Associated Press contributed to this report.