Colorado Republican leaders are mounting a concerted effort to quell dissension in their ranks ahead of a Saturday vote on whether to cancel the party’s 2018 primary for Congress, governor and other elected offices.

A coalition of Republican activists on the party’s governing body is attempting to block the state’s 1.4 million unaffiliated voters from casting ballots to pick the party’s candidates — a move GOP leaders and elected officials oppose because it could hurt their chances in the all-important November election.

Colorado will allow unaffiliated voters to participate in the June party primaries for the first time in June 2018 under Proposition 108, but the new law allows political parties to opt out, cancel the primary and instead select candidates through a caucus process.

Republican Party Chairman Jeff Hays is leading the opposition to the opt-out movement and enlisting support from U.S. Rep. Ken Buck, Secretary of State Wayne Williams and former party chief Dick Wadhams.

If the party opts out, it would also make it harder for the state’s 1.1 million Republican voters to participate. In 2016, only 60,000 party members participated in the caucus vote.

“Even though I’ve struggled with this issue, I think it’s best for the party to move forward and consent to the will of Coloradans,” Buck wrote in a recent email sent to the party’s governing body. “To disregard the voters would potentially hurt our statewide candidates in the upcoming election and would embody the back-room dealing our party stands against.”

The question is whether it’s too late.

The Colorado Democratic Party rejected the idea outright earlier this year, saying even the vote could alienate independent voters. If the GOP cancels the primary, it would only provide Democrats with political fodder.

And Republican leaders acknowledge that if the party doesn’t vote overwhelmingly to keep the primary, it could hurt their candidates’ chances to court unaffiliated voters.

“We need to kill this thing,” said Wadhams, the party’s chairman from 2007 to 2011. “If it comes close to 50 percent, I do think it is an embarrassment for the party.”

The party’s state central committee will meet early Saturday in Englewood to take a vote. To opt out, it takes the agreement of 75 percent of the 490 voting members of the committee — an intentionally high bar written into the 2016 ballot measure. It’s even possible the party won’t even get that many members or proxy votes to the meeting.

Ahead of the meeting, the Republican Party is sponsoring a forum at its fall fundraising dinner Friday to allow a debate on the issue. Williams and Wadhams are prepared the make the case against. Ben Nicholas, a party activist from Adams County, and George Athanasopoulos, a losing candidate for party chairman, will argue in favor of canceling the primary.

Nicholas said strong lobbying from party leaders against his opt-out campaign means one thing. “I’m probably going to be the main course to be served that night. I have the feeling I’m going into the lion’s den that Daniel did,” he said, referencing the Bible.

He said he’s running his campaign on “a wing and a prayer” but suggests the effort from party leaders in recent weeks shows that “the establishment Republican group is becoming a little nervous that we may be reaching into the high percentile (vote) that they don’t want us to hit.”

Nicholas’ argument, he says, is simple: Republicans don’t support open borders in the immigration debate, so why does it support allowing nonparty members to pick its candidates? “The analogy is the same in my mind,” he said.

The top Republican candidates for governor are entering the debate, with businessman Doug Robinson, district attorney George Brauchler and businessman and former state Rep. Victor Mitchell all opposed to opting out. State Treasurer Walker Stapleton, who is expected to enter the race soon, did not respond for comment.

2018 candidates for Colorado governor Who is running for governor of Colorado in 2018? (And who is on the fence?)

“The Republican Party should not shut itself off from any citizen who wants to participate in the process,” Robinson said in a statement. “Proposition 108 passed by a clear majority, and our party will be shooting itself in the foot if it chooses to turn away unaffiliated voters while our opponents embrace them.”

Brauchler said he opposed the ballot measure but supports the will of the voters. “I’m a firm believer that if you are not on the team, you ought not have input on who the quarterback is going to be,” said Brauchler, who opposed Proposition 108. But, he added, it would “end up disenfranchising Republicans” who would vote in the primary but not attend the caucus.