DNC delegates are jubilant about Harris. They’re also looking past the convention with caution.

Democrats are excited about Kamala Harris. Like, put-her-face-on-a-T-shirt-and-her-name-on-their-custom-Chucks excited.

But as thousands of delegates prepare to descend on Chicago for next week’s Democratic National Convention, their enthusiasm for the vice president and her running mate, Minnesota Gov. Tim Walz, is already becoming tempered by a recognition that the landscape following the convention could just as easily shift against them. Their overriding optimism, according to interviews with more than three dozen delegates, is tinged with caution.

The war in Gaza remains unresolved, as does the unrest over it at home — and there are fears among some Democrats that protests expected at their convention could flare up once again on college campuses as students return for the fall semester.

Inflation is ticking down, but the labor market is cooling . The recent stock market plunge — and recovery — reminded Democrats how quickly public perceptions of the economy can shift. Immigration remains a weakness for Democrats. And then there’s former President Donald Trump, who has struggled to find his footing against a new opponent but whose favorability ratings, while lower than Harris', have ticked up in recent weeks. His allies are now releasing a barrage of advertising against Harris .

“There’s this sense that the Democrats still haven’t done enough or connected enough with voters in the middle. And I think that anger is still out there, and it can sort of easily be captured by Donald Trump’s ‘let’s break apart the whole system because it’s not working for you,’” said Jamie Eldridge, a progressive Massachusetts state senator and delegate who had called in July for President Joe Biden to step aside from the top of the ticket. “I still have serious concerns that this is such a close election.”

Some delegates warned that the party cannot let the sugar high of a fundraising and polling surge for Harris’ campaign wear off once the convention is in the rearview.

“We can’t just get lazy and assume we’re going to have a big party and we’re going to get Democrats elected,” said New York Assemblymember Grace Lee.

Harris and Walz have acknowledged the challenges that lie ahead in a contest that remains extremely close in surveys and is still likely to be decided at the margins.

“I’m not naive. This is going to be hard. This is a hard race,” Walz said at a recent fundraiser in Boston. “But don’t underestimate the sense of joy that's starting to emanate from this.”

And Democrats are joyful. It’s a dramatic change in tone from the despondence that pervaded the party and its convention delegates just one month ago as Biden’s reelection bid sputtered to an end after a disastrous debate performance.

Now, they’re heading to Chicago for the party’s biggest gathering in eight years — one that delegates in interviews with POLITICO near-universally predicted would be Democrats’ most unified and optimistic national confab since Barack Obama’s first coronation in 2008. That is in no small part due to its similarly historic nature: Harris is the first Black woman and first South Asian woman to secure a major-party nomination. (Harris and Walz have already been certified as Democrats’ presidential and vice presidential nominees, though a ceremonial roll call is planned.)

It’s also an organic offshoot of happy-warrior messaging from Harris and, to an even greater extent, Walz.

“What the past few months ha[ve] taught me was that the Democrats didn't have a messaging problem. We had a messenger problem,” said David Crowley, a Wisconsin delegate and Milwaukee County executive.

The euphoria, delegates said, also represents a marked change from Democrats’ mood heading into the party’s last two conventions, both of which occurred after contentious primaries that fractured the party — and one of which was heavily altered by the pandemic.

"2016 was a feeling of coming off this uncomfortable and really tough primary, it was a kind of shotgun marriage. 2020 — it was in the middle of the pandemic, everyone was at home, there was a lack of an interconnected feeling,” said Brandon Zavala, a California delegate and veteran Democratic strategist from Los Angeles County who co-chairs the state Democratic Party’s organizing committee.

Now, he said, “it’s a chance to celebrate.”

Florida delegate and DNC member Samantha Hope Herring said her daughter, who is also a delegate, designed “Coconut Caucus” badges for the Florida delegation to wear around the convention — a reference to Harris’ viral “coconut tree” clip that has become a calling card of her campaign. Massachusetts delegates, meanwhile, will sport custom Harris-themed Converse (the sneaker brand is headquartered in the state). And one Harris County, Texas, delegate, Debby Kerner, plans to wear a T-shirt with the slogan “This is Harris County” next to an image of the vice president and the outline of Texas.

But delegates’ merriment will be pockmarked by protests, too. Tens of thousands of demonstrators are expected to flood the streets of Chicago, where at least six protest marches and rallies are planned. The coalition of nearly 200 groups plans to protest on a range of issues, especially the pro-Palestinian effort.

And inside the United Center will be some 30 “uncommitted” delegates — the product of protest votes during the primaries over Biden’s support for Israel and his administration’s continued aiding of the country in its ongoing war in Gaza. Those delegates could now prove a prime-time headache for Harris as they urge her to support an arms embargo of Israel.

Asma Mohammed, one of the 11 “uncommitted” delegates Minnesota is sending to the convention, said her mission is to persuade other delegates that a policy shift from Harris on the Israel-Hamas war is required to win the so-called Blue Wall states of Michigan, Wisconsin and Pennsylvania.

“We cannot win against Trump if we don't have all the uncommitted voters,” Mohammed said. “We will have a party that is split if we do not tackle this issue head on.”

Their calls will be amplified by symbolic “ceasefire delegates” — conventiongoers who have signed a petition calling for a cease-fire in Gaza and a cessation of munitions to Israel. That includes David Seaton, a Massachusetts delegate who is supporting Harris and praised her more “empathetic” approach to the situation — she met briefly with members of the uncommitted movement before a rally in Michigan earlier this month and has called for a cease-fire and a two-state solution — but remains concerned that she will not be able to win over younger voters who are supportive of the Palestinian movement.

And Pat Fahy, a New York alternate delegate attending the convention and Democratic candidate for the state Senate, is worried that further escalation in the Middle East could fuel another round of campus demonstrations this fall — developments that could undermine Harris’ campaign.

“We’re coming up on the anniversary of Oct. 7. I think the Middle East is still very much a concern,” she said.

While many delegates surveyed by POLITICO said they were not concerned about disruptions at and around the convention, some warned that they could be detrimental to both Harris and their cause.

“If anyone tries to cause any disunity, you’re just trying to play right into the hands of Donald Trump,” said Jim Demers, a New Hampshire delegate and longtime Democratic strategist in the state.

Beyond the conflict in the Middle East, delegates expressed a desire for Harris to flesh out her policy platform — particularly on the economy and border security, two issues that Trump is hammering Democrats on. Harris took a stab at the former Friday, unveiling a sweeping proposal that would crack down on price-gouging and lower medical costs while expanding affordable housing and child tax credits — aims that will be largely dependent on who controls Congress. Her plan, an extension of Biden’s policies, quickly won praise from some delegates. But concerns linger about her ability to sell both her plans and the administration’s economic wins, especially if the market takes another downward turn.

In Texas, Mary Alice Palacios, a delegate from the state’s Hidalgo County — a border county that Biden carried by 17 percentage points four years ago — said she wants Harris to lean into “harsher punishment for people bringing in illegal drugs across our border.”

And in New York, Linda Rosenthal, a delegate and state Assemblymember from Manhattan, said there is lingering anxiety of a post-convention October surprise on par with FBI Director James Comey reopening an investigation into Hillary Clinton’s email use while secretary of State during the 2016 election.

“Absolutely the vibes have shifted,” she said. “I get stopped on the street by random people and say it’s so exciting. People are so excited. They’re beyond elated. It speaks to how everyone was down in the dumps before.”

Still, Rosenthal said, “When you look at headlines that say the FBI is investigating hacking — I think after Chicago people will start to worry about things like that.”

Shia Kapos and Jeff Coltin contributed to this report.