Antonio Sabato Jr., left, and Scott Baio will speak at the Republican National Convention. (Chris Pizzello/Invision/AP; Amy Sussman/Invision/AP)

The Republican National Convention has quite the line-up of speakers tonight in Cleveland. Not only is Scott Baio speaking, but so is Antonio Sabato Jr.

Wait, who?

It’s okay to ask. It’s been a while since either of these guys were relevant, and we’re using the term “relevant” pretty loosely. So here’s a refresher for who your big convention speakers are.

[What happened in Chicago in 1968, and why is everyone talking about it now?]

Who is Scott Baio?

He’s most famous for playing Chachi on “Happy Days” — less so for the short-lived spinoff “Joanie Loves Chachi” — and the title character on the quintessential 1980s sitcom “Charles in Charge.” Charles was a college kid who moved in with a family to work as the nanny to their three kids. (No word on whether his best pal Buddy will be watching from the audience for emotional support.) Baio also starred in the 1976 gangster musical “Bugsy Malone” opposite Jodie Foster. That was the one with kids in all the roles. You remember, right?

Millennials may be more likely to know Baio from “Arrested Development,” where he played blogging lawyer Bob Loblaw. He also bears more than a passing resemblance to Bojack Horseman, although, you know, less equine.

He must be really into politics, too, right?

Pretty much. He revealed to Glenn Beck that he’s campaigned for Ronald Reagan and George H.W. Bush, and he likes to get political on Twitter. Yep, he’s one of those. Although that sometimes gets him into trouble.

Sample tweet:

“Taxes are DONE…That should feed, house & provide medical for a few lazy non working people at my expense. Have a great Monday!”

He also once tweeted a less-than-flattering photo of Michelle Obama with the caption: “WOW He wakes up to this every morning.” Classy stuff.

He recently went on Fox News to publicly proclaim his support for Donald Trump. “When he speaks I understand him,” Baio said. “He speaks like I speak.” He also commended Trump on his willingness to get down and dirty.

“We need somebody to relentlessly, relentlessly attack Hillary, and that’s the only way we’re gonna win, because this getting above the fray and not getting in the dirt and ‘we’re better than that,’ it doesn’t work anymore. But to win elections nowadays, the Democrats and liberals attack viciously.”

[Clinton vs. Trump: Whose celebrities are better? A scrupulously fair analysis.]

"Happy Days" actor Scott Baio spoke at Republican National Convention calling Republican presidential candidate Donald Trump "a man who knows how to get things done." (Victoria Walker/The Washington Post)

How did he end up speaking at the Republican convention?

That’s a good question. According to Baio, Trump asked him in a seemingly spontaneous way. Baio told Fox News’ Jeanine Pirro that he was at a fundraiser for Trump, and when the candidate was leaving, Baio intercepted him. “I looked at him and said, ‘Mr. Trump, Scott Baio,’ and he goes, ‘Oh my God,’ and he said to me, ‘Did you want to speak?’ and I went, ‘Here?’ and he goes, ‘No, no, no, at the convention.'”

There’s also the issue of Trump’s lack of starry support. While Hillary counts Lena Dunham and Beyoncé among her endorsements, Trump has Tila Tequila and Jean-Claude Van Damme. Who else could Trump have possibly tapped? Loose cannon Gary Busey?

Not likely. After all, would Busey do this?

Who is Antonio Sabato Jr.?

First of all, he was born in Italy and immigrated with his parents to the U.S. when he was a teen. Let that sink in.

Now fast-forward a few years: Sabato burst onto the scene in 1990, as the Cute Dimples Guy From That Janet Jackson Video. This should jog your memory. (He’s the guy who isn’t isn’t Djimon Hounsou.)

Before that, Sabato (and Hounsou, incidentally) had been a Calvin Klein model. But that silent, smiling cameo was enough to get the aspiring actor a role on “General Hospital” as fan-favorite Jagger Cates. Has there ever been a more soap-opera name? Then he transitioned to prime time with a recurring part on “Melrose Place” as Jack Parezi, Amanda Woodward’s malevolent estranged husband. Spoiler: He died after a dramatic balcony fall.

He’s bounced around since then, reprising his role as Jagger on “General Hospital: Night Shift” in 2008 and doing a two-year stint on “The Bold and the Beautiful.” He has also taken advantage of the reality TV industry, with guest appearances on everything from “Dancing With the Stars” in 2014 (he finished eighth) to “Celebrity Wife Swap.”

What about his politics?

He formally endorsed Trump in April, and posted a photo of the pair together on Instagram, proclaiming himself part of the #trumptrain.

https://www.instagram.com/p/BA1lpPbsnBG/

He’s also a prolific Twitter user, who like to bash Clinton and Obama on social media. He even suggested that the two should be imprisoned at Guantanamo.

He was more restrained during a recent interview.

Soap opera star Antonio Sabato Jr. spoke at the Republican National Convention supporting Republican presidential candidate Donald Trump and calling for secure borders. (The Washington Post)

“It is refreshing to have a candidate like Trump who is so honest about his feelings because he speaks for many of us when he says we are in a bad place,” Sabato told People. “I have never been a Republican or Democrat. I am an American.”

So why is he speaking?

Why else? Look at those dimples.

Here are some of the people who are speaking at the 2016 Republican National Convention in Cleveland and some who've opted to skip the event. (Sarah Parnass,Danielle Kunitz/The Washington Post)