Even though the Colorado Constitution already requires voters to be U.S. citizens, a citizens' initiative effort to clarify that wording is expected to submit signatures today to get a measure onto the 2020 ballot.

That effort, which is nearly identical to other proposals being considered in a handful of states, would change the state's Constitution from saying that "every citizen" of the United States has the right to vote in Colorado elections, to "only a citizen" can vote.

Supporters of the proposal say the change is needed to make it clear that voters must be U.S. citizens, while opponents say it's nothing more than an attempt to drive conservative voters to the ballot next year.

Joe Stengel, a former Republican state representative from Littleton, said there's ambiguity in the state's Constitution and in court interpretation of the definition between being a citizen or merely being a resident.

"You brought up that the Colorado Constitution seems to be very clear, well, if you read it, it is not clear," Stengel said. "What constitutes a resident under the statue, you will see that is it up to a municipality to determine residency. We are essentially taking out all of the room for error and interpretation."

Currently, the Constitution requires a voter to be a U.S. citizen and a resident of the state, but Stengel said a person only has to live in Colorado 22 days to be considered a resident.

He said some municipalities elsewhere in the nation have determined that any resident can vote in local elections, opening it up to non-citizens to cast ballots.

The campaign behind the measure, Colorado Citizen Voters, is expected to turn in more than 220,000 signature to the Colorado Secretary of State's Office today. The effort only needs 124,632 signatures from registered voters to qualify for the ballot.

Stengel said the campaign did get the required 2% signatures from each of the state's 35 Colorado Senate districts, as required under Amendment 71, approved by Colorado voters in 2016. That same amendment also says that any ballot measure that alters the Constitution needs at least 55% to pass.

A similar measure passed in North Dakota last year with nearly 66% of the vote. Nearly identical measures have been cleared to be on the ballot next year in Florida and Alabama, with a dozen other states looking at the idea, too.

The effort primarily is being funded by a Florida-based group called Citizen Voters Inc., a nonprofit organization formed by John and Gina Loudon, who are members of Trump's Mar-a-Lago Club. John Loudon is a former GOP state representative from Missouri, and Gina Loudon is a member of the Trump campaign's media advisory board and co-chairwoman of Women for Trump.

John Loudon is chairman of the Florida ballot campaign, and his wife, also known as the television and radio personality host Dr. Gina, is the author of a book that described the president as "the most sound-minded person to ever occupy the White House."

Citizens Voters Inc., has given the Colorado campaign nearly $1.4 million in in-kind contributions, primarily in hiring paid circulators to gather petition signatures.

Stengel, who served as minority leader in the Colorado House before leaving office in 2006, denied that the effort has anything to do with politics.

"It's a non-partisan issue," he said. "Democrats, Republicans, independents should all be concerned about voter integrity. Opponents can say whatever they want, but who would not be in favor of voter integrity?"