ASSOCIATED PRESS The Republican Convention Rules Committee Thursday shut down attempts to change the rules to let delegates vote their conscience. It was the last real opportunity for Republicans to deny Trump the presidential nomination.

CLEVELAND ― Republicans’ last realistic chance to deny Donald Trump their presidential nomination fizzled Thursday, as a key rules change proposal failed to get enough votes to reach the convention floor next week.

Leaders of the Free the Delegates group needed 28 votes of the 112-member Convention Rules Committee to force the full Republican National Convention to consider their “conscience clause.”

Instead, the most group leader and Colorado delegate Kendal Unruh could muster was about 21.

“Donald Trump is the presumptive nominee. There should be absolutely no question as to who we vote for,” said Arizona delegate Bruce Ash.

How many votes Unruh had exactly isn’t known, because she failed to demand a recorded vote before the chairman ruled it closed. On a previous vote by Trump supporters to shut down debate on her proposal, the vote was 77-21.

The vote followed weeks of a publicity campaign and lobbying effort by Unruh’s Free the Delegates and the supporting Delegates Unbound group. Unruh made her final appeal to her fellow 111 committee members, telling them her proposal restored their right to vote their conscience.

“That is a God-given right that shouldn’t be taken away by the RNC or any state,” she said.

When she began a public campaign to stop Trump last month, she had hoped for 57 votes, a majority. With that kind of backing, she believed she could have won over a majority of the 2,472 total delegates to support the rule, which in turn would have ended Trump’s chances.

In the past couple of weeks, though, Unruh downgraded her goal to 28 votes, enough for a “minority report” from the Convention Rules Committee. That would have carried far less weight on the convention floor, but still would have guaranteed a floor vote.

The Trump campaign and RNC leaders wanted to avoid a public display of internal party strife at the convention, which they hope instead to choreograph as a show of unity behind their nominee. They lobbied delegates to oppose Unruh and back Trump.

Utah Sen. Mike Lee, a delegate and a Trump critic, pleaded with Trump to recognize why so many are uneasy with him and to do something to mend fences. “This angst isn’t going to go away just because we papered over it with rules,” Lee said. “I say to Mr. Trump, and those aligned with him, make the case to those delegates who want to have a voice.”

It’s unclear whether Lee will get a response that offers him much comfort. At about the same time that Lee was speaking in committee late Thursday, Trump campaign chairman Paul Manafort was sending this Tweet: “Anti-Trump people get crushed at Rules Committee. It was never in doubt: Convention will honor will of people & nominate @realdonaldtrump.”

The “conscience clause” proposal was just one of dozens of rules changes the committee considered Thursday. The panel touched off hours of intrigue as it began by taking an hours-long break ― at first explained away as caused by a jammed printer, but eventually conceded as an attempt to cut a deal with some rules-change sponsors to save time.

“Obviously we did not stand adjourned for three hours for a jammed copier,” committee chairwoman Enid Mickelsen said when the panel finally began its work after lunch.

Those hours were spent trying to appease Ken Cuccinelli, the former Virginia attorney general and ally of Texas Sen. Ted Cruz, who pushed attempts to weaken the RNC chairman as well as to encourage states to restrict participation in primaries to keep out non-Republicans. Many conservative Republicans believe that independents and even Democrats have too much influence in choosing their nominee, thanks to open primaries.

But Cuccinelli said that after a day and a half of negotiations, the deal fell apart. “The RNC pulled out of it,” he told reporters afterward, blaming the impasse on how many bonus delegates states that hold closed primaries would get.

Cuccinelli wanted a 20 percent bonus, while the RNC came back with an offer of no higher than about 6 percent, he said. “They yanked it. They changed the numbers,” he said.

RNC strategist Sean Spicer said the negotiations were far more complicated than that, involving a number of disparate issues. As to the bonus delegate number: “Ken Cuccinelli doesn’t get to decide,” Spicer said, adding that other stakeholders had different views.

With the deal gone, the committee went through each of the elements of the proposed package one by one. Proposals to take away the power of the RNC to change its rules outside of a nominating convention and the ban on lobbyists took about an hour each. Both failed overwhelmingly.

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims ― 1.6 billion members of an entire religion ― from entering the U.S.