As Republicans flail from ‘one stupid jackass thing to another’, Harris strives to define vision

As Kamala Harris accepted the Democratic nomination for US president, and 100,000 red, white and blue balloons floated down from the rafters, Charlene Dukes' eyes filled with tears. "It was when she spoke about her family, her upbringing, which is so similar to many of us," said Dukes, a Black woman from Maryland.

"Many of us were not born with a silver spoon in our mouths," added Dukes, who said the prospect of the US electing a woman of colour as president for the first time in its 248-year history left her feeling "euphoric".

Harris's address got a thunderous reception in a packed sports arena in Chicago on Thursday night, crowning a pitch-perfect week for Democrats and whirlwind month that turned the presidential election on its head. Some had feared a repeat of the chaotic and violent 1968 convention in the same city; instead the feelgood factor was closer to the 2008 version in Denver that anointed Barack Obama.

In speech after speech, party leaders characterised Harris as a historic figure, the embodiment of hope, "the president of joy" - and predicted that she would defeat Donald Trump's "politics of darkness" once and for all. Delegates walked the streets of Chicago in idyllic weather with a spring in their step, thrilled that their party had been rejuvenated and revivified.

But having preached to the converted, Harris is about to face a tougher crowd. Even after six weeks in which everything went right, she enjoys only a fragile lead in opinion polls entering the final sprint. Trump has urged his supporters to "Fight! Fight! Fight!" Harris told hers: "When we fight, we win!" Now both are facing the fight of their political lives.

Democrats are not only buoyed up by their new ticket of Harris and running mate Tim Walz, the governor of Minnesota with dad, football coach and midwestern appeal: after years of soaring prices, the Federal Reserve has nearly conquered inflation without triggering a recession, a feat few economists predicted.

The number of people crossings into the US has fallen dramatically since Joe Biden's asylum crackdown and stricter enforcement in Mexico, although migration can be cyclical and, as the weather cools, it is possible the numbers will begin to climb.

Despite the positive trend lines, across the four-night arc of the convention, Democrats' most prominent voices cautioned against overconfidence. Michelle Obama, the former first lady, told delegates: "No matter how good we feel tonight, or tomorrow, or the next day, this is going to be an uphill battle."

Ex-president Bill Clinton, whose wife Hillary's bid to become the first female president was thwarted by Trump in 2016, added: "We've seen more than one election slip away from us when we thought it couldn't happen, when people got distracted by phony issues or overconfident."

Implicit in the warning words was the question hanging over the convention: can the Harris honeymoon last?

More than a month after 81-year-old Biden stepped aside and endorsed her, Harris has barely started to outline detailed plans that she would pursue as president to address challenges such as immigration, crime and the climate crisis.

She faces a crunch test on 10 September when she goes head to head with Trump, a notoriously unorthodox opponent, in a televised debate. As Biden discovered in June, a bad debate performance can change the entire trajectory of a race.

Harris has also yet to hold a press conference or give an in-depth media interview to face difficult questions about her leadership style, her significantly changed policy positions in recent years, and the focus on gender and race that looms over her historic candidacy - a topic she was careful to swerve past in her acceptance speech.

John Anzalone, a pollster who has worked for the last three Democratic presidential nominees, said: "We can't put our heads in the sand. She's a Black woman. The bar is going to be higher for everything and guess what that means: even mistakes are going to be magnified. Every campaign is going to have mistakes."

Harris's allies acknowledge that she remains largely undefined in the minds of many voters, having operated in Biden's shadow for much of the last four years. The relative anonymity offers both opportunity and risk.

David Axelrod, a former senior adviser to Barack Obama, said: "The thing about vice-presidents, the downside is, nobody knows who you are. The upside is, nobody knows who you are and so you get a chance to define yourselves."

Speaking on a panel organised by the University of Chicago's Institute of Politics and the Cook Political Report on the sidelines of the convention, Axelrod added: "She is a turn-the-page candidate, and the fight right now is whether the Trump folks can push her back into the box of being an incumbent and hold her accountable for the things that Biden has done, or whether she can continue on this path as the choice to turn the page."

Harris used her acceptance speech to promise to pass a middle-class tax cut, support Ukraine and Nato, and push for a ceasefire in Israel's war in Gaza. But for now, her team feels no urgency to publish a comprehensive policy platform or sit for media interviews that might jeopardize positive vibes that have produced a flood of campaign donations and a growing army of swing-state volunteers.

During a series of meetings throughout the convention week, her advisers cast her policy agenda as a continuation and expansion on Biden's first-term achievements, though at times with a different emphasis. While Biden spoke often of job numbers, Harris has focused on the cost of living and proposed a ban on price gouging.

Harris has also dropped opposition to fracking and support for Medicare for All, which were defining features of her doomed 2020 presidential campaign. Her aides insist her values remain the same but that she has embraced more moderate policies out of pragmatism. Progressives are also looking for clues that she will take a tougher line against Israel over its war in Gaza.

Sarah Longwell, a Republican strategist and Trump critic, said: "The extent to which she has been able to shake off Biden's negatives immediately has been incredible. She doesn't own his economy, as best I can tell, and she doesn't own Gaza. This is where I've been generally impressed with her and where Biden struggled as a communicator. These are complicated issues that require nuanced explanations and she's capable of giving those explanations."

The campaign promises a clash of styles. A former prosecutor, Harris devoted a broad chunk of Thursday's speech to nailing Trump's narcissism, hostility toward women's reproductive freedom and embrace of autocrats. "Just imagine Donald Trump with no guardrails," she said.

But numerous other Democrats used mockery and ridicule to make Trump seem small, likening him to a spurned boyfriend, a neighbour who keeps running his leaf blower and a tenor warming up with "Me me me me me". Walz has led the way in branding Trump and his allies "weird".

For his part, the former president has been struggling to find an effective line of attack. The Republican nominee has adopted a kitchen-sink approach against Harris that includes attacks about her racial identity ("Is she Indian or she is Black?"), her intelligence ("stupid", "dumb"), her laugh, her record as vice-president and her history as a "San Francisco liberal".

Longwell, founder and publisher of the Bulwark website, added: "'San Francisco liberal' is a buzzword that [for] conservatives strikes right at their hearts. Or even people who are centre-right. People know exactly what it means - and by that I mean they have no idea what it means but they understand what it feels like and it's bad, so that is the thing she's got to push off."

Frustrated Republicans have gone public to urge Trump to focus on policy rather than identity politics. They argue that he still enjoys the upper hand on immigration and inflation, although Harris has closed the gap in polling. But the Trump campaign is still struggling to adapt to its new, younger opponent.

James Carville, a longtime Democratic strategist, said: "The thing that's most amazed me is how utterly caught off-guard they were and how they still can't seem to get their sea legs. They can't settle on an attack. Fox [News] is just lost - they go from one stupid jackass thing to another stupid jackass thing."

Speaking after a tour of the Abraham Lincoln Book Shop in Chicago, Carville added: "Can they get it back? Maybe, sure, good chance. But right now they're spitting blood. They've been hit in the mouth. I'm hoping that the country decides we just want something different and has, believe it or not, something different."

The Trump campaign had been structured to attack Biden's age and mental acuity. The switch to Harris has turned the tables, with Trump, 78, the oldest major party nominee in history and Harris, 59, representing a fresh start.

Patrick Gaspard, a former official in the Obama White House, said at a media event organised by Bloomberg: "They are pretzeling themselves trying to figure out how to attack Kamala Harris because she has this powerful and unique and interesting advantage that we have never seen before in our politics. She is an incumbent but she's also a change candidate right now in this election. She's been able to seize the banner away from Donald Trump."

Gaspard, who has known Harris since the 2007-8 Obama campaign and describes her as a "Swiss army knife" able to appeal to voters in every context, added: "The Republican party will struggle for the next 75 days to impose some governing discipline on Donald Trump, [the US representative] Marjorie Taylor Greene and many others who are going to continue to go after Kamala Harris with misogynistic, racist, ethnic, xenophobic tropes.

"They're going to struggle with that and they're going to fail miserably because [Trump] is a candidate who is incapable of being conditioned to a new kind of behaviour. There is no message discipline there. The challenge that they have: Donald Trump is a far better candidate in 2016 than the guy who's standing on the stage today."

But in a deeply divided country, the election remains too close to call. Not even an attempted assassination or change of nominee has moved the needle more than a few percentage points. Independent candidate Robert F Kennedy Jr's decision to suspend his campaign and endorse Trump will not be a gamechanger either.

Most people have made up their minds. According to an ABC News/ Washington Post/Ipsos survey, just 12% of voters are potentially persuadable this election, and they tend to be less engaged: roughly one in four of them say they are certain to vote in November compared with nearly two-thirds of Americans overall.

Dan Kanninen, battleground director for the Harris-Walz campaign, told reporters at a Bloomberg event that the electoral map has neither expanded nor shrunk since Biden's withdrawal: "The race is not fundamentally changed. The enthusiasm is incredible. The fact we're connecting with some voters in different ways is obvious and shows up in some of the research that you're all seeing as well. But the race is still very, very tight."

Harris, who with Walz starts a bus tour of swing state Georgia on Wednesday, has clawed back the losses caused by Biden's low approval rating. But she has 11 weeks left to define herself not merely as the inheritor of the anti-Trump coalition but as an inspiring figure in her own right. Joy alone will not be enough.

Amy Walter, publisher and editor-in-chief of the Cook Political Report, said in an interview: "I don't think we're at a sugar high. Where she is now is where Democrats should be but it's not high enough to win. So to me the bigger question is not so much: 'Is all this enthusiasm going to go away?' as 'Is she going to be able to get beyond just the coalescing of the base and get that next 2, 3, 4%?'"

Asked whether she would dare to predict the outcome on 5 November, Walter gave a one-word answer. "No," she said, with a hearty laugh.