AMNA NAWAZ: Vice President Kamala Harris and former President Donald Trump are pressing ahead with a very busy campaign schedule.

For Mr. Trump, that included his first campaign appearance since the latest apparent assassination attempt against him.

Lisa Desjardins has the latest on the increasing calls for civility in this contentious election season.

MAN: Kamala Harris!

(CHEERING) (APPLAUSE) LISA DESJARDINS: In Washington for the start of Hispanic Heritage Month, Vice President Kamala Harris spoke to the Congressional Hispanic Caucus, weaving in campaign themes as she stressed the American dreams.

KAMALA HARRIS, Vice President of the United States (D) and U.S. Presidential Candidate: Our work together has always been guided by shared values and by a shared vision.

However, at this moment, we are confronting two very, very different visions for our nation, one focused on the past, the other, ours, focused on the future.

LISA DESJARDINS: She spoke to Latinos in Congress a day after she took questions from Black journalists, where she revealed she spoke to her rival, Donald Trump, following the apparent assassination attempt against him Sunday.

Republicans on Capitol Hill pulled no punches today, saying Harris and Democrats have not done enough to bring down temperatures.

REP. TOM EMMER (R-MN): Democrats so-called leaders and the partners in the media need to get a grip.

And the Secret Service can and should do more to protect President Trump.

We cannot normalize what has happened to an American president and our current Republican nominee.

LISA DESJARDINS: Democrats today reiterated that there is no place for political violence, but added a note for their Republican colleagues.

REP. PETE AGUILAR (D-CA): Let's also be very clear that when the other side of the aisle talks about this issue, they lack a lot of credibility with the American public.

(CHEERING) LISA DESJARDINS: For the former president, last night in his first campaign appearance since the second apparent attempt on his life, there was a notable change in tone.

He even thanked his opponents, saying their kindness made it harder to attack them.

DONALD TRUMP, Former President of the United States (R) and Current U.S. Presidential Candidate: President Biden, I want to be nice.

He was so nice to me yesterday.

But, in one way, I sort of wish the call wasn't made, because I do feel that he's so, so nice.

"I'm so sorry about what happened and all that."

But I have to lay it out.

We have very important -- and the same with Kamala today.

She could not have been nicer.

LISA DESJARDINS: Trump made light of the second apparent attempted assassination in as many months, saying that running for president is dangerous business.

And he remained defiant.

DONALD TRUMP: And then you wonder why I get shot at, right?

Only consequential presidents get shot at.

MAN: J.D.

Vance!

LISA DESJARDINS: On the trail today in North Carolina, Trump running mate J.D.

Vance praised the former president for being cool under pressure.

SEN. J.D.

VANCE (R-OH), Vice Presidential Candidate: You want the guy who's able to keep his heads about him even when literal gunshots are going off.

LISA DESJARDINS: In a significant move, the Teamsters union says it won't back either Harris or Trump.

That breaks with nearly three decades of endorsements, which have consistently been for Democrats.

DONALD TRUMP: It's a great honor.

They're not going to endorse the Democrats.

That's a big thing.

And this is the first time in, I guess, 50, 60 years that that's happened.

Democrats automatically have the Teamsters.

LISA DESJARDINS: Mr. Trump headlines a rally in New York tonight amid tight security.

The state is not seen as within reach for the former president, but several downballot House races are in play.