AMNA NAWAZ: Meanwhile, long before Chris Coons became a senator from the state of Delaware, he was a Capitol Hill intern for then-Senator Joe Biden.

We spoke about their decades-long friendship, the president's speech tonight, and much more when we sat down earlier today.

Senator Coons, welcome back to the "News Hour."

Thanks for being here.

SEN. CHRIS COONS (D-DE): Great to be here with you.

AMNA NAWAZ: Let's talk about your friend and this moment.

SEN. CHRIS COONS: Yes.

AMNA NAWAZ: Because, for someone who has spent 50 years of his life in public service, I think it's fair to say this is a complicated moment.

SEN. CHRIS COONS: Yes.

AMNA NAWAZ: When you talk to him, how is he viewing this moment right now?

SEN. CHRIS COONS: Well, he's optimistic.

He's looking forward.

He believes that Kamala Harris and Tim Walz are the best chance we have to secure our democracy.

When Joe announced he was running, four years ago at the Democratic Convention, when we kicked off the campaign against Donald Trump, he focused on restoring the soul of our nation.

I will remind you, we were in the middle of a terrible pandemic.

It was a virtual convention.

We were in the middle of an economic collapse, and just two weeks before he took the oath of office, there was January 6, an assault on our democracy.

Tonight, you're going to hear Joe Biden look back a little bit on just how much he's had to pull us through.

I'm going to speak a little bit about how this man, who's been knocked down by life so hard several times, helped us all get back up again, and how his courage, his belief in democracy and belief in all of us really is what underpins his incredibly selfless decision to step aside and let his trusted vice president carry the torch forward, hopefully, God willing, to electoral victory this November.

AMNA NAWAZ: You have known him for 35 years.

SEN. CHRIS COONS: I was an intern for Joe Biden in the Senate 35 years ago.

AMNA NAWAZ: And when he first made the decision to step aside, you got a little emotional as you talked about it for the first time.

SEN. CHRIS COONS: I did.

AMNA NAWAZ: Tell me what this moment is like for you, speaking before him, what you hope people take away from your remarks, and also understanding that this is not quite the speech he thought he'd be giving just a few weeks ago.

SEN. CHRIS COONS: I hope, when Joe Biden comes into the hall tonight, that he gets the longest, Loudest, most sustained cheers and applause, people jumping up and down and shouting, "We love you, Joe," of any president in our history.

There's been more conventions here in Chicago than any other American city.

And he deserves to know that the American people, certainly the Democratic Party, loves this man for all he's done for us.

AMNA NAWAZ: Is there any part of him that second-guesses his decision to step aside?

SEN. CHRIS COONS: Everybody second-guesses their decisions.

But the last few times we have spoken, he's really been focused on the future.

We spoke just a few days ago.

He was excited about the Cancer Moonshot event he was doing in Tulane.

Dr. Biden is focused on education, on women's health.

Together, they're focused on doing things for veterans' families, for military families.

They have got a lot more to do, not just in the final five months that he's president, but going forward.

And I'm excited to support them in that.

AMNA NAWAZ: We have seen this race shift dramatically in just a few weeks' time.

SEN. CHRIS COONS: Yes, strikingly.

AMNA NAWAZ: The party quickly coalesced around Vice President Harris as the candidate.

She set records for fund-raising.

You have seen battleground state polls now tied, her ahead with a narrow lead nationally.

And yet it's still a very tight race.

SEN. CHRIS COONS: It is.

AMNA NAWAZ: So where do you see the biggest challenge ahead for this ticket?

SEN. CHRIS COONS: Well, I think the American people need to really look at who these two candidates are.

Donald Trump has been really struggling to find his footing, and he chose an odd colleague of mine, J.D.

Vance, as his running mate.

And the two of them have some clear views.

Trump just said this past week he wants to slap a 20 percent tax, a tariff, on every imported good.

That would raise household costs by thousands and thousands of dollars, with no clear benefit, and would cost millions of jobs.

Kamala Harris and Joe Biden just signed, right, the announcement about 10 major pharmaceuticals coming down in price, things like Xarelto and Jardiance that we see a lot of ads for, 500 bucks a month down to 200 bucks a month, caps on insulin, caps on out-of-pocket costs.

What you're hearing from the Democratic leadership, from Kamala Harris and Tim Walz, ideas for how to reduce housing costs, reduce day care costs, reduce prescription drug costs for the middle class.

What you're hearing out of Donald Trump and J.D.

Vance is a willingness to abandon democracy overseas and let Russia take Ukraine and a lack of a commitment to the middle class here at home.

I'm hoping we get to have a campaign this fall that isn't just about personalities, but is about substance, because Joe Biden ran on substance and delivered substance.

AMNA NAWAZ: I know we're going to be hearing more about some of those policies from Harris and Walz this week as well.

But you're co-chair of their campaign.

SEN. CHRIS COONS: Right.

AMNA NAWAZ: You want to get them elected.

To do so, do you think that she needs to break with some of the policies of the Biden/Harris administration, especially issues like on Gaza, where we know there's hundreds of thousands of people who voted uncommitted in the primaries that this campaign needs to bring on board?

SEN. CHRIS COONS: One of the things that President Biden is working tirelessly on right now, where I'm hoping for a breakthrough this week, is the cease-fire deal that he took to the U.N. Security Council, to the G7, and is applying all the resources he's got from his diplomatic and national security advisers.

I'd love to see that happen while Joe Biden's our president.

But, frankly, Vice President Harris has made it clear that she will stand firm with defending Israel against attacks from terrorist groups, either from Iran or from Hamas or Hezbollah, but has also expressed serious concern about the humanitarian condition on the ground in Gaza and the need for us to make real progress in rebuilding Gaza.

AMNA NAWAZ: President Biden has five months left in office.

As you mentioned, he has a lot on his plate, this cease-fire deal potentially, continuing to get support to Ukraine and their war, this Cancer Moonshot as well.

What do you see ahead for him?

For someone who has spent basically his entire adult life in politics, in public service, what does the next chapter look like?

What do you see him doing?

SEN. CHRIS COONS: He can be an incredible resource for future American leaders.

I think he'd love to be a mentor, a guide and adviser to the next president, vice president, to members of the Cabinet, but, frankly, equally to people who are just getting started in national service, whether it's elected or just public service of all kinds.

AMNA NAWAZ: Senator Chris Coons, good luck on stage tonight.

Thank you so much for making the time.

SEN. CHRIS COONS: Thank you.