A refreshed Democratic Party reintroduces itself to a divided nation this week, having been transformed by the money, momentum, relief and even joy that followed Vice President Kamala Harris' rise to the top of its ticket.

The whiplash of the last month culminates in a convention that begins Monday in Chicago. Above all, the four-day gathering of thousands of activists and party leaders from across the nation is designed to celebrate and strengthen Harris as President Joe Biden's replacement and boost her campaign to defeat Republican Donald Trump in November.

Just beneath the surface, real questions loom about the depth of Harris' newfound support, the breadth of her coalition and the strength of her movement. Not even a month ago, Democrats were deeply divided over foreign policy, political strategy and Biden himself, who was holding on after his disastrous debate by suggesting he had a better chance than any Democrat — including Harris — of beating Trump.

Far from the formality that many modern party conventions have become, this week's event will bring many Americans their first extended look at Harris and her new running mate, Minnesota Gov. Tim Walz. How the Democrats present Harris and Walz will be critical, especially with Trump launching a weeklong effort to cut into their message.

A potential distraction will be thousands of progressive protesters who are expected to descend upon Chicago to decry the Biden-Harris administration’s support for Israel’s war against Hamas in Gaza. Harris’ allies are hopeful that the pro-Palestinian protesters will not overshadow the official program, which features a slate of current and former Democratic stars.

“Democrats are walking into that convention enthused, excited and unified,” said one of those stars, Pennsylvania Gov. Josh Shapiro, who was a finalist to be Harris' running mate. “And it’s critically important that we prosecute the case against Donald Trump and the chaos that he would bring — and leave that convention even more unified, even more excited, even more enthused for the final 75 or so days of this campaign.”

Shapiro said he welcomed protesters during the convention — “provided the protest is peaceful, provided the protest follows the rules of the community.”

Part of introducing Harris and Walz will be first giving a graceful exit to the 81-year-old incumbent president, who is slated to deliver the keynote address Monday.

The Democratic Party likely would have been in a far worse state if Biden had continued to cling to the nomination. He faced growing concerns about his mental and physical acuity after struggling to complete sentences at the debate.

By deciding to step aside and endorse Harris, the 81-year-old president will instead receive a hero's welcome in his final turn in the spotlight 52 years after being elected to the Senate from Delaware.

Biden is planning to give a lengthy endorsement of Harris and sharply criticize Trump before he leaves Chicago and makes way for the program to focus on the vice president he chose four years ago.

Trump has tried to inflame tensions over Biden's exit. He called Biden’s Monday speaking slot “convention death valley,” suggesting that the president would get lower ratings than speakers on other nights. And as he has for weeks now, Trump described the convention itself as “rigged” because is was Biden, not Harris, who won 14 million primary votes and collected delegates state by state.

To display this content from YouTube, you must enable advertisement tracking and audience measurement.

The convention will lean into the party's potential to make history. Harris vies to be the first woman, the first Black woman and the first person of South Asian descent to reach the Oval Office.

“I wasn’t sure I would see this particular moment in my lifetime, to see a Black woman who is now on the cusp of becoming our next president,” said Illinois Lt. Gov. Juliana Stratton, one of the nation’s highest-ranking Black women elected officials.

Stratton recalled Hillary Clinton's loss to Trump eight years ago, one in which she lost key battlegrounds even as she led the national popular vote.

“I remember back in 2016 when we touched the glass ceiling, and the reaction of Republicans was just to start destroying the rights that got us there,” Stratton said. “This is another chance.”

Harris will aim to use the convention to take a share of credit for what she and Biden accomplished while also trying to show that she recognizes voters want more. Heading into Chicago, she unveiled the initial planks of her policy platform focused on addressing the bite of inflation and the costs of food, housing and childcare.

Democrats will keep abortion access front and center for voters, betting that the issue will propel them to success as it has in other key races since the Supreme Court overturned Roe v. Wade two years ago.

Every living Democratic president and first lady will appear this week, except for the ailing Jimmy Carter, along with a long list of federal, state and local officials and activists.

It’s set to be a contrast to last month's GOP convention in Milwaukee, where former President George W. Bush and former vice president Mike Pence, among other well-known Republicans, stayed away from the event given Trump's antipathy toward them.

Expected to speak this week is former Rep. Adam Kinzinger, a Republican who investigated Trump’s actions around the Jan. 6 Capitol insurrection and has endorsed Harris.

With precious few days remaining before early voting begins in some places in September, recent polls show a close race nationally and in battleground states like Pennsylvania, Michigan and Wisconsin. And polls show Trump still has advantages on how Americans view the two of them on core issues like the economy and immigration.

Terry McAuliffe, a former Virginia governor and longtime operative who will attend his 13th Democratic convention this week, warned that the euphoria Democrats have about Harris' ascension could obscure the true state of the campaign.

He noted that the Republican convention in Milwaukee was a veritable Trump coronation, with Democrats consumed by anxiety and uncertainty. Now, it’s Trump who seems to be reeling as he searches for the right message to stop Harris’ rise.

The lesson, McAuliffe said, is never to assume the a campaign is settled and always remember the outcome rests on getting 270 Electoral College votes by winning the right battleground states.

The former president is not ceding this week to Democrats. He will go a different swing state each day — starting with Pennsylvania, followed by Michigan, North Carolina, Arizona and Nevada by week's end.

Trump’s campaign has also dispatched high-profile allies to Chicago to host daily news conferences. The lineup includes Florida Sen. Rick Scott, Wisconsin Sen. Ron Johnson and Florida Rep. Byron Donalds.

“We have four days of messaging that the country will get to look at Kamala Harris, get to look at Tim Walz. We’ll get to look at their agenda, what they stand for, who we are,” McAuliffe said. “It’s going to be a close election. That’s just where our country is today.”

Whatever happens this week, both sides will be watching with anticipation as Harris writes a new chapter in what has already been a precedent-breaking campaign.