Democrats have momentum – but how long will Harris honeymoon last?

What a difference a week makes.

The Republicans had been riding a wave of optimism. Yes, political parties expect a positive bump during and after their convention, but following the attempted assassination on Donald Trump and with so many questions swirling around Joe Biden’s ability to lead for another four years, the Republican Party felt more unified and confident than it had in years.

Then the news from the Oval Office. Biden was stepping aside and endorsing his vice president, Kamala Harris. In a matter of days, so did almost every other senior official in the party, Barack Obama the latest. The Democrats went from a party fearing defeat to feeling like they had the momentum. The Republicans had lost their mojo.

Speaking to voters in recent days in Pennsylvania and Ohio, it’s clear that Biden’s decision is something rare in modern American politics: it’s been hugely popular across the board, with one poll suggesting some nine in ten Americans approved of him stepping down.

The general sense since Harris became the presumptive Democratic nominee is that she has rejuvenated the party’s base, increasing support among Black and Hispanic voters, women, and the young. You could feel that in the room when she spoke to members of a Black sorority in Indianapolis. As she made her way out on stage, women across the vast hall leapt to their feet, phones aloft, some rushing forward to get a better look.

But if Democrats feel history, they are haunted by it too. While Obama’s two victories offered hope, Hillary Clinton’s loss still leaves a scar. One poll even suggests that Americans are less receptive to a female president now than in 2016. Eight years on, with another woman facing Donald Trump again, has anything changed?

Morgan Overton and Lauren Williams think so. Overton is the vice-chair of the Allegheny County Democratic Committee, while Williams leads the Young Democrats in the same county. Two young Black women, they are vital organisers come November. This county in Pennsylvania, which includes the city of Pittsburgh, is crucial for the party. Not enough Democrats came out here in 2016, but they did in 2020, tipping the state blue and securing the White House for Biden.

“I think what’s changed is that our voting base has gotten younger, right?” Williams says. “I was 16 when Hillary Clinton ran. I couldn’t vote for her. I’m 24 now. I can vote for Kamala Harris.”

Overton adds: “Millennials and Gen Z voters combined make the largest voting bloc. We are so ready to have a reflective democracy. And Kamala Harris is it.”

Williams picks up on a key shift. Before Harris entered the race, commentators were calling this the “double haters” election because so many Americans disapproved of both Biden and Trump. “I think swing voters were upset with the idea of another 2020 rematch,” Williams says. “But with Harris on the ticket, this is different, this is new. We haven’t seen this before. And I think that’s what gets them off the couch to go vote for Harris in November.”

The polls are narrowing, but that does not mean Harris is the favourite. Barack Obama’s endorsement of her is a reminder of the coalition he built to win in 2008 and 2012. The big question for Democrats is not just about energising their base, but whether college-educated white women will come out and vote (because of issues like abortion access) or if they can sustain the level of support among working-class and older white voters that Biden managed.

In Ohio, Obama won the state twice, but it has not gone blue since. At the Butler County fair, in a suburb sandwiched between the cities of Cincinnati and Dayton, people were gathering for a Demolition Derby. These are the white voters that show the strength of Trump’s appeal, but also the message that concerns many across the country: the economy.

John Allspach is clutching his McDonalds while he watches mangled cars get yet more mangled. “I think we were all doing better when Trump was in charge and these last four years have kind of kicked us in the butt,” he says.

“When Democrats got into office, everything just went higher and higher and higher,” Andy Webster tells me. I ask him whether Harris can do anything to change his opinion. “She’s part of the evil. She’s part of the problem.”

There are many Trump supporters here, such as Andrea Koehne, who is 18 and will vote for the first time this year. She told me that she did not think America was ready for a female president.

It’s worth remembering that despite Trump’s appeal, he is still an unpopular candidate. Michelle Swagler said she did not like him, calling him a “moron”. Josh Hubbard said he wanted to do more research on Harris, believing that she has “a decent track record” and “a lot of experience”.

And amid the swirl of political opinion, I found one person who might also need to do a bit more reading around Harris. When I asked Patricia Bell what she made of the vice president, she told me: “I don’t even know who that is!”

It is clear Harris has had a good first week, but she still has work to do. And that’s why many commentators believe her choice for running mate could be crucial. For those wavering or yet to fully commit, who she picks could seal the deal.

It’s 100 days until the election.