Rep. Tom Suozzi, a moderate Democrat who flipped a New York district held by ousted Rep. George Santos, campaigned heavily on immigration and messaging that the Democrats should be tougher on the issue.

But Suozzi told ABC News on Monday he's happy with how Vice President Kamala Harris has handled the key 2024 issue so far.

"She came out early in this campaign and continues to talk about how she would have supported the bipartisan Senate deal to secure the border. Now, I think we're going to hear more and more details about securing the border, fixing the asylum system and helping those people that have been here for decades, that have played by the rules to try and lift them up," Suozzi said.

When asked if he's spoken with Harris since she began her presidential bid, Suozzi said he has not but has spoken with her team. Suozzi is also set to speak at the convention this week.

On the ticket as a whole, Suozzi told ABC News: "I feel great. I'm so excited about this ticket. I'm excited by the enthusiasm I see from the voters, not only in my district, but throughout the country."

-ABC News' Oren Oppenheim

During a walk-through at the United Center ahead of his speech tonight, President Joe Biden said he was ready to pass the torch.

"Are you ready to pass the torch, sir?" a reporter asked from the floor while Biden did his stage check.

"I am," Biden answered from the podium, where he'll speak later tonight.

In response to questions about his message, he said: "You'll hear it tonight."

-ABC News' Cheyenne Haslett

Rep. Dean Phillips, a former 2024 Democratic presidential candidate who was the first congressional Democrat to question Biden's candidacy, appeared on ABC News Live to discuss the state of the election since Biden dropped out of the race.

ABC News' Kyra Phillips asked the Minnesota congressman if he felt like he deserved an apology for being the first to say Biden should leave this race.

"Just walking into this room today ... that's the only apology I needed," he replied, adding: "It's the energy, the excitement. I was just begging for a party to listen. ... I don't need an apology. What I need is for us to win, and it feels pretty darn good here today."

Rep. Phillips said this convention "is a passing of the torch to the new generation. I think people want to leave here feeling something."

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Rep. Dean Phillips was 1st congressional Democrat to question Biden candidacy

The Minnesota lawmaker didn't receive much praise for calling on President Joe Biden to end his re-election campaign. He joins the show to discuss what's occurred since Biden dropped out of the race.

-ABC News' Isabella Meneses

President Joe Biden was seen doing a stage check Monday afternoon at the United Center in preparation for his opening night speech.