GEOFF BENNETT: Welcome to the "News Hour."

The second night of the Republican National Convention is about to get under way.

AMNA NAWAZ: The convention picked off last night with former President Donald Trump's first public appearance since he was nearly killed.

Lisa Desjardins is on the convention floor with a closer look at the stirring start to the week here in Milwaukee.

LISA DESJARDINS: It was quite a dramatic moment last night, of course, when the former president arrived here.

He now joins his newly minted vice presidential nominee, J.D.

Vance.

And I will show you guys, as predicted, here are the first Trump/Vance signs.

All of this is part of one message that, this is a strong and confident Republican Party.

ANNOUNCER: Please welcome the next president of the United States.

LISA DESJARDINS: A grand entrance and triumphant return.

The GOP's nominee for a third time, Donald Trump, appeared on the first night of the Republican National Convention in Milwaukee, walking into his family box at the Fiserv Forum to thunderous applause.

It was his first public appearance since the attempt on his life, a white bandage on his right ear a vivid reminder of how close an assassination attempt came.

AUDIENCE: Fight!

Fight!

Fight!

Fight!

Fight!

Fight!

LISA DESJARDINS: The crowd chanted, "Fight," the same word Trump mouthed while being rushed off stage three days ago.

It was also the first public appearance of the new Republican ticket, as Trump stood with his new running mate, 39-year-old Ohio Senator J.D.

Vance, the youngest vice presidential nominee in a generation.

He's barely served two years in elected office.

His life is changed now.

A security detail walked with him and his family on a morning trip to Walgreens.

By afternoon, he was standing in the spot where he will speak for the Trump/Vance ticket tomorrow.

Vance was once a sharp Trump critic.

He addressed the change of heart on FOX News.

SEAN HANNITY, FOX News Anchor: You literally said -- you texted a friend that Trump is a cynical A-hole like Nixon, who wouldn't be that bad and might even prove useful, and that he's America's Hitler.

SEN. J.D.

VANCE (R-OH), Vice Presidential Candidate: Well, Sean, I don't hide from that.

I was certainly skeptical of Donald Trump in 2016.

But President Trump was a great president, and he changed my mind.

LISA DESJARDINS: Opening night started out relatively sedate, until South Carolina senator and former presidential candidate Tim Scott took stage.

SEN. TIM SCOTT (R-SC): On Saturday, the devil came to Pennsylvania holding a rifle, but an American lion got back up on his feet, and he roared!

(CHEERING AND APPLAUSE) LISA DESJARDINS: Scott was one of several prominent Black Republican men to speak yesterday.

Polls show Trump has made moderate gains with voters of color, and the campaign wants to firm up and improve their support, as does President Biden, back on the campaign trail for the first time since the Trump shooting courting Black voters at the NAACP's national convention in Las Vegas.

JOE BIDEN, President of the United States: So many of you had my back, and I think I have had yours as well.

LISA DESJARDINS: Yesterday on NBC, he addressed his words to donors that Trump should be in the -- quote -- "bullseye."

JOE BIDEN: It was a mistake to use the word.

I didn't say crosshairs.

I meant bullseye.

I meant focus on him.

I'm not the guy that refused to accept the outcome of the election.

I'm not the guy who said they wouldn't accept the outcome of this election automatically.

LISA DESJARDINS: While the GOP Convention has been forward-looking, there are ties to 2020 conspiracies and lies.

Several Republicans who served as fake electors are among the listed delegates.

A few other delegates were there on January 6 in the mob outside the Capitol.

And while Republicans have generally called for calmer tones, some remarks yesterday were sharp.

SEN. RON JOHNSON (R-WI): Today's Democrat agenda, their policies are a clear and present danger to America, to our institutions, our values and our people.

LISA DESJARDINS: Also last night, there were sharp identity politics.

Georgia Republican Representative Marjorie Taylor Greene lashed out against transgender and nonbinary Americans in her speech.

Tonight, we will hear from a different prominent Republican woman, Nikki Haley, the former U.N. ambassador, South Carolina governor, and, of course, the number two, the runner-up in this race for the nomination.

She will be speaking here tonight.

We will see what she says -- Amna, Geoff.

GEOFF BENNETT: Well, let's talk more about that, Lisa, because, initially, as you well know, Nikki Haley was not invited to even attend this convention, and now she's speaking.

And even after she dropped out of the primary, in some states, she was still pulling 20 percent of the Republican vote.

I know you spoke with some of her former delegates.

What are they telling you?

LISA DESJARDINS: I will tell you, the Haley delegates on this floor are all in for Trump, the ones that I have spoken to so far.

But there is still some discomfort between the two camps.

Speaking to some in the Trump universe, they say they wish she'd gotten out of the race sooner, that it was not respectful that she waited as long as she did to even say that she was voting for former President Trump.

Now, it's not just the delegates here that matter, of course, but Haley voters around the country.

And I caught up with two voters we talked to in January.

I want to show you a picture.

This is Dennis and Sherri Monsotter (ph).

They are military family, all in for Nikki Haley.

They will be watching tonight.

They have not decided, Geoff and Amna, if they can support Donald Trump.

They told me they're not sure about J.D.

Vance.

They're worried he's too isolationist.

They don't like the direction he's going in, and they want to see Trump move more toward Nikki Haley before he can get their support.

AMNA NAWAZ: Those are going to be key voters to keep an eye on there.

Lisa, also, you have been reporting on this idea that Republicans are going to be focused on another battle tonight.

That is for control of the U.S. Senate.

What should we expect?

LISA DESJARDINS: Right, a very big night, I have been told by people around this convention that we will hear from people like Kari Lake of Arizona trying to take a Senate seat from Democrats there, but all of the sort of key Democrats running for seats.

And that battle is critical, as will be the things, every one of those candidates says on stage tonight.

GEOFF BENNETT: The theme tonight, Lisa, is make America safe again.

Help us understand what the party is trying to convey with that messaging tonight.

LISA DESJARDINS: This will be a darker tone tonight.

This will be a night where Republicans will try to convince the public that President Biden has led to a country full of crime, where undocumented immigrants have been causing problems for communities across this country.

We know, of course, that violent crime in this country has gone down in the last couple of years.

There are some communities where that's different.

But, tonight, we have to pay very careful attention to how this tone goes, because this is trying to present kind of an atmosphere of fear.

Many of these delegates believe there is a reason to fear.

We know the statistics say otherwise, so we have to watch it carefully.

GEOFF BENNETT: And we should convey our apologies for talking through the prayer here on the floor.

These timing issues are outside of our control.

AMNA NAWAZ: Lisa, finally, we know also just a few hours ago we learned about reports that the Secret Service had increased security for the former president, former President Trump, due to a possible foreign threat.

What should we know about that?

LISA DESJARDINS: That's right.

We have learned, myself and producer Dan Sagalyn, from sources involved that the National Security Council has been tracking increased potential threat from the Iranian government against former President Trump because of the assassination strike he launched against a top Iranian official in 2020.

They conveyed that to the Secret Service.

Secret Service then surged its resources, but they say that was before the assassination attempt this weekend.

And they say they do not think that assassination attempt is connected.

AMNA NAWAZ: All right, that is our Lisa Desjardins down on the convention floor, where she will be all night for us as our special coverage continues.

Lisa, thank you.