Will the Republican National Convention, set to begin on 18 June, be the extravagant show that Donald Trump promises? So far it seems, that will be a difficult promise to keep. Several prominent Republicans have already announced they will skip the event, leaving many to wonder who will actually attend.

According to the Washington Post, the presumptive nominee will bring members of his family, former primary rivals and GOP leaders who are largely unknown. The RNC's lack of star power is a reflection of the party itself during this election season.

"Republicans have always had a terrible star-power deficit—the Democrats have the latest hip-hop or pop act and we've got lee Greenwood and the Oak Ridge Boys—but now it's going to be even more pronounced," Rick Wilson, a Republican strategist not supporting Trump, told the Post.

Democrats have largely stood behind their presumptive nominee, while Republicans remain divided as ever. "Bill Clinton, Hillary Clinton, Barack Obama, Michelle Obama, Elizabeth Warren—they're all going to be out there swinging for the fences. But the Republicans, it'll be like a hostage video of people forced on stage," Wilson said.

House Speak Paul Ryan, a wary supporter of Trump, appears to be the highest profile party leader attending the convention, according to The Post. Ryan will chair the convention and expects to give a 10-minute speech along with his ceremonial duties. The Post noted that Trump's wife, Melania, or his three adult children may also speak during the convention.

RNC 2016
Quicken Loans Arena is decorated to welcome the Republican National Convention on July 11, 2016 in Cleveland, Ohio. The convention will be held at the arena July 18-21, 2016.Getty Images

NBC News also revealed who else is expected to speak next week. Former rivals Senator Ted Cruz, Governor Mike Huckabee and Governor Scott Walker are set to speak. House Majority Leader Representative Kevin McCarthy will deliver an address about the House GOP's agenda and working on party unity.

Senators Tom Cotton, Mitch McConnell, Joni Ernst will appear, as will Representative Marsha Blackburn and Governor Asa Hutchinson. Frequent Trump defender and former New York City Mayor Rudy Giuliani, regular Trump rally opener pastor Mark Burns and Michigan Attorney General Bill Schuette are also set to address the RNC.

As for celebrities, Caitlyn Jenner, Kid Rock, Lynyrd Skynyrd, Rascal Flatts and Big & Rich will be in Cleveland.

But who will not be present? Both living former Republican presidents, George HW Bush and George W Bush, and the two last Republican nominees, Mitt Romney and John McCain, have said they will not go to this year's convention. Jeb Bush, son and brother to the former presidents, is also skipping the event.

The Post noted that the party's diverse young darlings—New Mexico Governor Susana Martinez, South Carolina Governor Nikki Haley, and Florida Senator Marco Rubio—will be no shows.

"The fact that the party elders aren't willing to come make his case says a lot about the state of the Republican Party," Bill Burton, a Democratic strategist, told the Post. "To the extent that Trump is having trouble getting speakers who can tell his story and tell the story he wants to tell about Hillary Clinton—it's a larger lift."

A complete list of speakers remains unknown, even to members of the Republican National Committee. "Donald Trump's run an unconventional campaign from the get-go and he said right from the outset he wanted an unconventional programme with not the usual speakers," said Steve Dupre, a New Hampshire RNC member. "Frankly, it might stir up more interest than parading our past luminaries of a party. Maybe the Trump way will work."

Voters will apparently have to wait and see.