On Super Tuesday, one million registered voters who live in Colorado won’t be able to participate in the caucuses that night because they are unaffiliated with a political party.

That’s right: one million.

Why? Because in Colorado, only registered members of major political parties can participate in the precinct-caucus process that helps pick a president. These caucuses are neighborhood gatherings held around the state where loyal Democrats and Republicans get together and discuss why they support their favored candidate. They then elect local delegates to carry the banner of their candidate through a series of conventions.

Related: Confused about the Colorado caucuses? Here’s the deal

What this means is that on Tuesday, while many registered Democrats and Republicans will go to caucuses around Colorado to help pick a president, the state’s largest voting bloc— those who are unaffiliated— will not be able to participate.

Why? Blame state law.

Two groups, however, have started a statewide conversation about changing the system, and one is pushing a ballot initiative to ask voters to change it themselves.

Building a Better Colorado, a bi-partisan group of political heavy hitters with support from Democratic Gov. John Hickenlooper and former Republican Attorney General John Suthers, tackled the question about caucuses versus primaries on its website and in sponsored Facebook ads that asked Coloradans on social media to weigh in. The group says 67 percent of new residents to Colorado decide to register as unaffiliated voters.

“Caucuses limit turnout among Republicans, Democrats and unaffiliated voters because they are held in the evening on a single day as opposed to the 22 days allotted for voting in a primary,” the group states on its website. And meanwhile, “Primary elections are paid for by all taxpayers, yet 37% of voters are effectively excluded.”

On that note, Tuesday might be a bruiser for a certain type of unaffiliated voter in Colorado. Because Vermont’s Bernie Sanders was the longest-serving Independent in the Senate, he could have support among a solid chunk of unaffiliated Colorado voters who didn’t switch their party registration to become registered Democrats by the Jan. 4 deadline. Also, this year the Republican Party leadership cancelled its official straw poll for president diminishing Colorado’s role in the presidential nominating process.

Related: Here’s how many unaffiliated voters became Dems before the Colorado deadline

But voters might one day soon have a say in whether the current system remains in place.

A group called Let Colorado Vote has taken formal steps to get a question on the ballot to voters in November, which, if passed, would change Colorado’s early nominating presidential contest system to a primary election that would allow unaffiliated voters to participate. Colorado would keep the caucus for nominating candidates to lower-level offices and for other party business.

“The measure would keep Colorado’s caucus nomination system in place for every office but president,” the group’s Joe Blake who is also chancellor emeritus of the Colorado State University System, said in a statement. “On that front, the current system draws lackluster interest from voters and candidates and, this year, Colorado Republican caucuses will not consider presidential candidates.”

Colorado’s current caucus-convention system is the traditional way Coloradans have voted throughout the state’s modern history, though there have been hiccups. For instance, in 1992 a state senator was able to get the state to switch to a party primary, and Colorado held primaries in 1992, 1996, and in 2000.

In 2008, Colorado went back to the caucus system and parties could conduct straw polls during presidential years. So in 2008 and 2012 Colorado Democrats and Republicans had a say in the early nominating contests for president; this year it’s just the Democrats because the Republicans cancelled theirs.

For Let Colorado Vote, it’s all about more people getting involved.

“The evidence from the two caucus states so far is that they severely limit participation,” says Curtis Hubbard, a spokesman for the group. He pointed to the caucus states of Iowa and Nevada where turnout was low.

“Our view is that a primary election in which somebody is mailed a ballot 22 days before the election will see significantly higher participation, particularly when Colorado’s one million unaffiliated voters are included,” he said.

Following a public event on Thursday, Hickenlooper said he’s heard about the ballot measure but wouldn’t say whether he’d support it. While Hickenlooper has been linked to Building a Better Colorado, the governor said, “I don’t support everything they support.”

Bob Loevy, a retired political science professor at Colorado College and an expert in presidential early nomination contests, says expanding the electorate to include unaffiliated voters in Colorado would weaken control of party leadership over the nominating process.

Asked what they thought of allowing unaffiliated voters to participate in a different kind of early nominating process for president here, the top brass at the state Democratic and Republican parties weren’t entirely enthusiastic.

The Republican Party of Colorado would be open to a system allowing unaffiliated voters to participate, but only if the voter would automatically become a registered Republican once their ballot is cast in a Republican early nominating contest, according to Chairman Steve House.

Colorado Democratic Party chairman Rick Palacio, who opposes the ballot measures, says unaffiliated voters can already participate.

“They just have to change their affiliation, and they can change it back after the process,” he says. He’s also concerned campaigns would have to raise and spend more money than they already do trying to target potential voters in elections, increasing the flood of money and political ads to Colorado.

Hubbard maintains it shouldn’t be any more difficult for an unaffiliated voter to participate than a Democrat or a Republican.

As for Loevy, the professor, he’s all for allowing more people to have a voice in the process, and feels the current system is confounding to many.

“There is a colossal lack of information and understanding of how the system works in the political leadership in Colorado,” he says.

[Photo credit: Robert Couse-Baker via Creative Commons on Flickr]