Donald Trump signs a magazine with his picture on it at a campaign rally in Raleigh, N.C., on July 5, 2016. (Reuters/Joshua Roberts)

Republican convention delegates hoping to snatch the party's presidential nomination from Donald Trump are still coming up short.

Leaders of "Free the Delegates," a coalition of various groups hoping to stop Trump at the Republican convention in Cleveland this month, conceded Tuesday night that they're far short of the votes needed to change GOP presidential nomination rules and reopen the battle.

"It’s just continuing to be the uphill battle that I knew it would be," said Kendal Unruh, a group leader.

Despite near-daily conversations with delegates worried about Trump's presumed nomination, "There’s just a lot of pressure, a lot of fear, a lot of ‘I’m with you in theory, but I’m trying to get the courage to come out and support it,’" she told group members on a weekly conference call.

Unruh is a member of the 112-member convention rules committee, which will determine exactly how Trump will be formally nominated by the party. The panel's meetings are scheduled to begin July 14 and could run as long as three days, depending on how long it takes to debate potential rules changes.

Unruh would need at least 56 votes to approve her proposal to allow delegates to vote however they want, instead of being bound to the results of state caucuses and primaries. After that, a majority of the convention's delegates would need to vote for her plan when the party meeting opens on July 18.

But Unruh's idea has the public support of less than 10 members of the rules panel, according to a Washington Post tally of delegates.

Given those odds, “Courage is not in excess” among delegates, another group leader, Dane Waters lamented on the call.

Trump has dismissed attempts to unseat him as "illegal" and has a team of up to 150 paid staffers and volunteers preparing to thwart any attempt to stop him at the convention. Four of his top convention lieutenants are on the rules committee and prepared to help stop Unruh's proposal, according to campaign aides familiar with the plans.

Unruh and Waters are part of a small, but vocal group of GOP activists who believe that national Republican leaders have bucked long-standing rules that grant presidential nomination powers only to convention delegates. They argue that as members of a private association, only they can ultimately decide who the party nominates.

Unlikely to prevail in the rules committee, Free the Delegates is now focused on a federal court challenge set to be considered on Thursday in Virginia.

Carroll "Beau" Correll, one of Virginia's 49 GOP convention delegates, filed suit in federal court in Richmond on June 24 challenging a state law binding him to the results of the March 1 primary. He supported the presidential campaign of Sen. Ted Cruz (R-Tex.). His suit argues that the state law binding him to the primary results violates his First Amendment right to vote his "conscience, free from government compulsion."

"States shouldn’t be compelling members of a private organization" to vote a certain way, Correll told the conference call on Tuesday night. He said a favorable court ruling could eventually strike down laws binding convention delegates to the results of caucuses and primaries and "send a resonating message to about 20 states" that have such laws.

A group of eight Virginia delegates, backed by the Trump campaign, intervened in Correll's case by asking the judge to dismiss the challenge. Virginia Attorney General Mark Herring has said he will defend the current state law in court.

Given the increasingly daunting odds facing the group, leaders brought in two prominent conservative voices to buck up the rank-and-file.

Bill Kristol, editor of The Weekly Standard and one of Trump's most vocal critics, encouraged the group to keep looking for support -- even though his own highly publicized attempts to stop the candidate have sputtered.

"I think we’re on the right side of history as well as on the right side of rejecting someone who shouldn’t be the nominee of the Republican Party," he said.

Kristol openly encouraged the delegates to spark "floor fights," if they disagree with the proceedings.

"It’s not going to be chaos any more than the 1860 Republican Convention that nominated Lincoln on, I think, the third ballot," he said, adding later: "It’s not going to be chaotic and I think it could be a good exercise in representative democracy. It’s unusual, but it’s an unusual year with unusual circumstances."

Kristol was joined by David A. French, an attorney and National Review staff writer who briefly considered but rebuffed Kristol's calls to run as an independent presidential candidate.

If Free the Delegates succeeds, they'd be leading "A rebellion on the behalf of the majority – let’s remember that – the majority of Republican voters who rejected Trump," he said. The group "would literally rescue the party of Lincoln from making a potentially fatal mistake. The nomination of Donald Trump stands to alienate such a large percentage of the American population that the GOP may never rescue itself from minority status in this country."