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.

A march organized in support of Palestinians in Gaza during the DNC has started, hours before its first night of programming kicks off.

Organizers with the Coalition to March on the DNC, which represents more than 200 activist organizations, said about 15,000 people were present for a rally held in Union Park, near the convention site, ahead of the march.

Biden continues to "fine tune" his speech after working on it over the weekend and is in "great spirits" as he heads to the convention, White House press secretary Karine Jean-Pierre told reporters aboard Air Force One.

"Yeah, look, the president is certainly going to continue to fine tune the speech, if you will. He had an opportunity to work on it this past weekend with Mike Donilon and Vinay Reddy, and so he's very much looking forward to this moment. As I just said, it is a fulfilling moment for him, and he's excited. He's excited," Jean-Pierre said.

"It's a big night. He's looking forward to it. He's looking forward to addressing the Democratic Party and and obviously the nation. It's a big night," she added

Jean-Pierre said Biden was in a good mood on the plane ride over.

"He's in great spirits and I think what you'll see is a president who has put his kind of his personal agenda aside and putting the country first, and that's who he's always been throughout his career, more than 50 years," Jean-Pierre said.

Read more about what observers expect from Biden's opening night speech here.

-ABC News' Cheyenne Haslett