House Speaker Paul Ryan will be talking at the convention about the GOP agenda in the lower chamber, focusing on "the sharp contrast" between Republican ideas and four more years of Obama-like progressive policies; and the need for conservatives to unite around Republican candidates in advance of a critical election," a Ryan aide told Politico.

Ryan endorsed Trump in June -- while he said they have a lot of common ground, he has also said, "We're going to agree to disagree on some things." The speaker disagreed with Trump's Muslim entry ban proposal and his comments about the judge in the Trump U case, Gonzalo Curiel.

Senate Majority Leader Mitch McConnell of Kentucky, who has previously criticized Trump on a number of issues, told CNN in a July 12 interview that he would be a speaker at the party's national convention in Cleveland. He did not give details about his speech.

The Senate majority leader late last month implied that Trump wasn't yet ready for his race against Hillary Clinton. "Trump clearly needs to change, in my opinion, to win the general election," McConnell said in an interview with Time Warner Cable News.

Sen. Tom Cotton, R-Arkansas, told MSNBC Wednesday that he is expected to address Republicans at their national convention.

"I do intend to be speaking at the convention," Cotton said. "I look forward to talking about our military and our veterans and what we need to do to make sure that we're serving them so they can serve us."

Michigan Attorney General Bill Schuette will speak at the first session of the Cleveland convention, according to the Detroit Free Press.

Schuette, who chairs the Republican Attorneys General Association, has criticized Trump before, calling the candidate's comments about Trump "deplorable." But Schuette, who was chairman of Jeb Bush's campaign in Michigan, has also said he was "going to support the nominee."

Wisconsin Gov. Scott Walker will speak at the convention, local station WKOW reported in early July.

"I think there is a clear contrast," Walker to WKOW. "For those who raise concerns like I just did about the judgment of Hillary Clinton in terms of not just those emails, but some of the other issues out there, really there's only one alternative."

Walker's endorsement of Trump in July did not actually name him. "Last August, I said I'd support the GOP nominee," he tweeted. "It's now clear who the RNC delegates will vote to nominate. And he is better than she is."

New Jersey Gov. Chris Christie, once Trump's presidential primary rival, was the first major establishment Republican to endorse Trump, and he was among the final contenders for the veep spot. been out on the campaign trail with Trump more than any of the other contenders.

"I'm certainly looking at him and I always will. Whether it's for that or something else," Trump told conservative radio host Howie Carr of Christie, who was the first governor to endorse Trump shortly after he dropped out of the White House race.

Sen. Joni Ernst, R-Iowa, will address the Republican convention in a speech focused on national security.

Ernst, whose name has been floated as possible vice presidential pick for Trump, told Politico that she would decline a spot on the ticket if it were offered.

"I made that very clear to him that I'm focused on Iowa. I feel that I have a lot more to do in the United States Senate. And Iowa is where my heart is," Ernst said. "I'm just getting started here. I have a great partner with Chuck Grassley, we've been able to accomplish a lot. And I think that President Trump will need some great assistance in the United States Senate and I can provide that."

Retired Indiana University basketball coach Bobby Knight has given Trump his full-throated endorsement, and has even campaigned with the real estate mogul on numerous occasions.

In one controversial endorsement statement, Knight even suggested that Trump would have the "guts" to drop a nuclear bomb on America's enemies, much like President Harry Truman.

"Harry Truman, with what he did in dropping and having the guts to drop the bomb in 1944, saved, saved millions of American lives," the basketball icon added. "And that's what Harry Truman did and he became one of the three great presidents of the United States. And here's a man who would do the same thing because he's going to become one of the four great presidents of the United States."

Knight will be addressing the convention via video.

Texas Sen. Ted Cruz, Trump's one-time rival in the primary race, agreed to speak at the convention after meeting privately with Donald Trump last week.

"Donald asked me to speak at the Republican convention, and I told him I'd be happy to do so," Cruz told reporters after Trump's "positive and productive" visit to Capitol Hill. As for the contents of his speech, Cruz said he would "urge Americans to get back to the Constitution."

Cruz, who will be the only Hispanic persona addressing the RNC, has not endorsed Trump.

Several key members of Trump's family, who serve as top campaign advisers, will be speaking, including wife Melania Trump, and his children Ivanka, Eric, Tiffany, and Donald Trump Jr.

There are also several names who have connections to Trump's corporate side, including Kerry Woolard of Trump's Virginia winery and the VP to the Eric Trump Foundation Lynne Patton.

Florida Attorney General Pam Bondi dropped an inquiry into Donald Trump's troubled Trump University despite complaints from citizens, according to internal documents reviewed by The Associated Press.

PayPal co-founder and former CEO Peter Thiel is a delegate for Donald Trump. The famed Silicon Valley venture capitalist will be speaking at the convention. He last made headlines when it was revealed that he had secretly bankrolled former pro wrestler Hulk Hogan's lawsuit against Gawker.

Thiel, according to the Associated Press, may be the first openly gay speaker at a Republican convention.

Oklahoma Gov. Mary Fallin had been talked about as a possible running mate in Trump's veepstakes. The conservative female Republican is slated to speak during the fourth night of the convention.

Former Speaker of the House Newt Gingrich, a top contender as Trump's running mate, will speak at the convention on its third night. Gingrich campaigned with Trump earlier this month.

Arkansas Gov. Asa Hutchinson is scheduled to speak on the second night of the GOP convention. Hutchinson, who endorsed Florida Sen. Marco Rubio in the Republican primary, officially gave his support to Trump in early May.

Lt. Gen. Michael Flynn, a former director of the Defense Intelligence Agency, is a lifelong Democrat -- but Trump considered putting the retired general on the Republican ticket to bolster the national security credentials on the Republican ticket.

According to a Washington Post report, the billionaire said that a Trump-Flynn ticket is "a brand he finds appealing."

Alabama Sen. Jeff Sessions was Trump's first Senate endorsement, announcing his support for the billionaire in February when he joined Trump at a Madison, Alabama rally.

During that event, Sessions donned a "Make America Great Again" hat and declared, of Trump's following: "There is a movement afoot that must not fade away."

Since then, he's been an informal adviser to Trump. Sessions is counted among the most conservative senators -- he largely shares Trump's views on immigration and has defended him and urged his Hill colleagues to get behind Trump's presidential candidacy. The Alabama senator is also a former U.S. attorney who was nominated to the bench but was never confirmed. Sessions was among those being considered by the Trump as a running mate.

In April, ahead of New York's primary, former New York City mayor Rudy Giuliani came out in support of Trump. Giuliani has found favor with the billionaire this campaign season, and Trump even once proposed that the ex-mayor should head up a commission on fighting radical Islamic terrorists. Now, the one-time 2012 presidential candidate will address the GOP convention on Trump's behalf.

Liberty University president and pastor Jerry Falwell Jr. will speak at the Republican convention, along with other faith leaders, like Rabbi Haskel Lookstein and African American Pastor Mark Burns. Falwell, an evangelical icon, endorsed Trump back in January.

Former Arkansas Gov. Mike Huckabee, a former rival of Trump's in the Republican primary contest, will address the convention. Huckabee endorsed Trump in May after dropping out of the White House race.

Several Republican members of Congress are slated to speak at the GOP convention, including House Majority Leader Kevin McCarthy of California, Texas Rep. Michael McCaul, Tennessee Rep. Marsha Blackburn, New York Rep. Chris Collins, and Montana Rep. Ryan Zinke.

Republican National Committee Chairman Reince Priebus has worked hard to unite the party behind Trump, despite a brutal primary battle that seemed to deeply divide top Republican figures. Priebus will address the convention of the fourth night.

Florida Gov. Rick Scott endorsed Trump after he won a resounding victory in the Sunshine State. Scott called on Republicans to unify in preparation for the general election. He will be a speaker at the convention's fourth night.

Actor Scott Baio will be addressing the convention -- he's well-known for roles in "Happy Days," "Joanie Loves Chachi, "Arrested Development," and "See Dad Run." As a young actor, he campaigned for Ronald Reagan. Baio endorsed Donald Trump in March, telling Fox News that he liked the way Trump communicates. "When he speaks I understand him," Baio said. "He speaks like I speak, he communicates with people very well. I want him, as any one person can do, to go into Washington and blow it up."

Scott Baio at the 2012 TeenNick HALO Awards, Hollywood Palladium, Hollywood, CA 11-17-12; Shutterstock ID 119346010; Job: CBS News/Candy Factory

Sen. Ron Johnson, R-Wisconsin was personally invited to speak by Reince Priebus, which was first reported by Politico. Johnson's topic is national security, and he'll only be at the convention on Tuesday -- the day he's speaking -- so that he can go home and campaign for his reelection.

U.S. Sen. Ron Johnson (R-WI) speaks during a pancake breakfast for Republican Presidential candidate, former Massachusetts Gov. Mitt Romney at Bluemound Gardens on April 1, 2012 in Milwaukee, Wisconsin.

There are several notable political figures that won't be speaking in Cleveland, including some who are avid supporters of the presumptive GOP nominee.

Former Alaska Gov. Sarah Palin, who endorsed Trump early and has appeared on the campaign trail with him numerous times, does not have a scheduled speaker slot. And Indiana Gov. Mike Pence, a top contender for Trump's running mate, also won't be speaking -- a sign that he could likely be Trump's No. 2 pick.

No former presidents will be speaking at the convention, and no former Republican nominees.

Two soap opera stars will be speaking at the convention: actor Antonio Sabato Jr. of "General Hospital" and Kimberlin Brown of "The Young and the Restless" and "The Bold and the Beautiful." Sabato has also been on numerous reality television shows, including "Celebrity Wife Swap," "Dancing with the Stars," and "My Antonio."

Presumptive Republican presidential nominee Donald Trump will conclude the convention.