In their first presidential debate, former United States President Donald Trump and Vice President Kamala Harris both accused each other of fuelling division in America.

The candidates quickly dived into contentious issues, from migration and fracking to Israel’s war on Gaza, but there were no groans or rapturous applause as the pair spoke without a live audience at the National Constitution Center (NCC) in Philadelphia, Pennsylvania.

Around the country, though, millions of Americans watched on from their living rooms or watch parties in bars and clubs, while outside the official debate venue in Philadelphia, protesters called for Harris to earn their vote with a ceasefire in Gaza.

With pre-debate polls placing Democratic candidate Harris and Republican candidate Trump neck and neck in the race, Al Jazeera spoke to political observers from across the country about who were the biggest winners and losers on the night.

Barbara Perry, a presidential historian at the University of Virginia:

Perry said, “Trump supporters received plenty of red meat to devour.

“The vice president offered a clear contrast between the specifics of her policies for the future compared to Trump’s generalities about the dark past, as he sees it.

“Kamala Harris needed to give undecided, moderate voters who are persuadable in the swing states a comfortable reason to cast their ballot for her.

“At the very least, she didn’t put those voters off or make any disqualifying gaffes. And she earned Taylor Swift’s endorsement,” Perry said, referring to a statement from the pop superstar right after the debate, where she said she would vote for Harris in November.

Michelle Austin Pamies, a Haitian-American leader and lawyer from South Florida:

Paimes said it was good that the “ugliness” of Republicans’ debunked claims about Haitian immigrants were revealed.

“It is clear that the former president wants to promote this idea that in Springfield, Ohio immigrants are eating pets,” she said referring to a comment that Trump made about Haitian immigrants in the debate.

“I thought it was good that it was it was discussed in the presidential debate, because I thought the ugliness deserved to be noted.

“I think the only reason that was brought up is because it was the most repulsive thing that could be said. And I just feel that it’s a way of othering that is very, very disgusting.

“I did appreciate the fact that the moderator clearly stated that it’s not a fact, that the city manager stated that there was no credible reporting of any such activity.”

Protesters rally for a ceasefire in Gaza near the debate venue in Philadelphia, Pennsylvania [Eduardo Munoz/Reuters]

Reem Abuelhaj, spokesperson for No Ceasefire No Vote Pennsylvania:

Abuelhaj said protesters outside the venue overwhelmingly “felt that they were unable to cast their ballot for a candidate who is actively supporting genocide”.

“Vice President Harris has been pretty clear in previous statements, as she was tonight, that she will continue Biden’s policy of unconditional military and financial support for Israel’s war on Gaza.

“Pennsylvania is a key swing state. There [were] 60,000 people, Democratic voters, who chose the write in option in a primary rather than cast their ballot for President Biden.

“Tonight, what was clear was that there is rage and grief across the city of Philadelphia and across the state of Pennsylvania, that this genocide is ongoing, and that the US is continuing to fund and arm the genocide.”

John Feehery, Republican strategist: 

Feehery said moderators “were clearly more keyed up on fact-checking Trump” and “didn’t really fact-check Kamala Harris, who had a bunch of whoppers throughout the whole debate”.

“I think that on style points, I would give the edge to Harris.

“She was, I think, nervous at the beginning, but she seemed to get her stride, and after that, it was just kind of a both sides were kind of wailing away at each other.

“I’m not sure if that’s what the voters necessarily want. I think they want a better plan on how to fix the economy, I think that’s what they most care about.”

Kelly Dittmar, director of research at the Center for American Women and Politics, Rutgers University-Camden:

Dittmar said Harris was able to “bait Trump into unravelling” while “responding to criticism that she has not been substantive enough on policy – scrutiny that has historically been greater for women than men in politics”.

“Trump refused to look at Harris, which could land differently for different groups of voters but could easily be viewed as dismissive in ways that don’t land well with women.

“Harris often looked and spoke directly to Trump, demonstrating no fear of direct engagement.

“While some will criticise her emotive facial expressions, others will see her clear expressions of confusion and concern over Trump’s statements as resonant with their own emotions during the debate.”

A watch party in Shawnee, Kansas [Charlie Riedel/AP Photo]

Aaron Kall, director of debate at the University of Michigan:

Kall said Tuesday’s debate was “unrecognisable” from “what we witnessed in Atlanta a few months ago,” referring to the June debate between Trump and President Joe Biden, who subsequently dropped out of the race.

But Kall cautioned against reading too much into the impact of the debate on the November election.

“While Harris was victorious in the debate by a slight nod, it remains unclear if this will impact the overall trajectory of the race or if there will be any movement among undecided voters.”

Shannon Smith, executive director for FracTracker Alliance, from Pittsburgh, Pennsylvania:

Smith said the debate showed there is still a lack of political will from either party to address the environmental and health effects of fracking.

“Living in one of the top fracked gas-producing states, Pennsylvania residents have endured years of increased fracking activity without political leadership to put common-sense protective measures in place.

“Tonight’s debate demonstrated that this lack of political will continues, regardless of which political party you associate with.

“An abundance of peer-reviewed research shows that fracking cannot be done without negative impacts to people, the environment and the climate.

“Environmental and climate impacts know no political boundaries.

“We need leadership that will prioritise public health and safety and craft sensible energy policy around it.”