Denver (CNN) Donald Trump is turning to his family, sports figures and business leaders to fill speaking slots at the Republican National Convention later this month as scores of prominent Republican leaders continue to refuse to line up behind their controversial nominee-to-be.

Trump announced Friday that his wife and children "are all going to be speaking" at the nominating convention that kicks off in just over two weeks. And the real estate mogul has also promised to add sports figures and other non-politicians who are supporting him to the roster of convention speakers, which would set the 2016 convention apart from past conventions packed with current and former elected officials.

The unconventional programming, which Trump has said will include a "winners' night," comes as his campaign and the Republican National Committee are facing an unusual problem unseen in past conventions: a lack of interest in speaking slots from many party elders and rising stars.

Instead of bartering with former primary rivals and the next generation of party leaders jostling for prominent placement in the convention programming, Trump is left watching idly as prominent Republicans tell reporters they have no interest in speaking at the convention or, in some cases, even just attending.

"Everybody normally wants to speak at the convention," said Stuart Stevens, chief strategist to Mitt Romney's 2012 presidential bid who was involved in organizing that year's convention.

A bevy of senators, prominent congressmen and governors have stated that they won't attend the convention , refusals that are particularly pronounced among those facing tight re-election battles in battleground states.

The past two GOP nominees, Romney and Sen. John McCain of Arizona, have also said they won't attend the convention in Cleveland. And several of Trump's GOP rivals, including the host state's governor, John Kasich, also won't take the stage at the convention.

"Trump is the most unpopular politician on the national scene. So the idea that a lot of people aren't dying to appear with him shouldn't be a shock," Stevens said, pointing to Trump's sky-high unfavorable numbers, which have hovered around 60% in the latest polls.

Trump tweeted Saturday morning that there was no shortage of speakers for the convention and that he would soon reveal their names.

"The speakers slots at the Republican Convention are totally filled, with a long waiting list of those that want to speak - Wednesday release," Trump said.

The speakers slots at the Republican Convention are totally filled, with a long waiting list of those that want to speak - Wednesday release — Donald J. Trump (@realDonaldTrump) July 2, 2016

Rather than try and mend fences to woo some of his former rivals and members of Congress who are critical of his candidacy, Trump has entrenched himself and taken again to criticizing many of his fellow Republicans in recent weeks, including threatening to go it alone in the general election if others don't line up behind him.

"We have to have our Republicans either stick together or let me just do it by myself. I'll do very well," Trump said at a recent rally in Atlanta. "Just please be quiet. Don't talk. Please be quiet. Just be quiet to the leaders because they have to get tougher, they have to get sharper, they have to get smarter."

Republican National Committee spokeswoman Lindsay Walters said many of the politicians who have said they won't attend have never participated in a convention and wouldn't necessarily be expected to attend.

Walters added that those up for re-election who won't attend would rather spend time in their districts, "shaking hands of voters," rather than attending the party convention in Cleveland.

Trump will still have a well of prominent supporters and party favorites to pull from, but the campaign is working to line up speakers -- both political and non-political types -- and Trump has been intimately involved in approving and nixing ideas for the convention, a source familiar with the planning told CNN.

Ben Carson, Trump's primary rival turned trusted surrogate, will speak at the convention, another source said.

But the big ticket invitations have been slow to roll in. Trump's call to invite Carson came Thursday -- just over two weeks before the convention kicks off -- and Trump told The New York Times in an interview published Friday that he is still mulling which sports figures to invite and has yet to call them.

A night of speeches from prominent sports figures and business leaders could help the presumptive Republican nominee compensate for his lack of powerhouse Republican speakers and help bolster his outsider image.

The "winners' night" Trump has promised would be jam-packed with sports figures supportive of his candidacy, and he has floated such big names as New England Patriots quarterback Tom Brady, UFC President Dana White and NASCAR CEO Brian France.

"I'm thinking about getting some of the great sports people I know, who like me a lot," Trump said at a rally in Richmond, Virginia, last month.

"We're thinking about doing something that's different," he said a week later at a Dallas rally.

Trump's daughter, Ivanka, has said that the atypical lineup will make for "a convention unlike any we've ever seen."

"It's not gonna be a ho-hum lineup of the typical politicians," she said in an interview with radio host John Fredericks, the conservative radio host. "It's gonna be a great combination of our great politicians, but also great American businessmen and women and leaders across industry and leaders across really all the sectors, from athletes to coaches and everything in between."

But Trump is facing difficulties lining up speakers even among the non-politicians who support him and whom Trump would like to speak at the convention.

Former Chicago Bears coach Mike Ditka, who supports Trump, said Wednesday Trump called to invite him but said he likely won't attend.

"Giving a speech at a convention isn't really my style," Ditka told the Chicago Tribune

But Stevens, the former Romney strategist who is deeply critical of Trump, said the convention -- an affair, typically designed to give the nominee a bump in the polls and define political coverage for a week -- won't be a defining moment for the Trump campaign, regardless of its outcome.

That's because the Democratic convention will swoop into the news cycle days after the Republican one wraps up.

"He'll get a little bump and then the Democratic convention will come," Stevens said. "And then the race will reset."