Kamala Harris was the clear winner of Tuesday night's presidential debate, according to our snap poll of independent voters, who declared her the most presidential candidate and Donald Trump the most aggressive.

Some 49 percent said Harris gave the better performance, while 43 percent said Trump came out on top.

However, the online poll of 800 independent voters suggested that the 90-minute debate may not have changed many minds.

Harris added only two points to her overall support. While 36 percent said they planned to vote for Harris before the debate, the figure was 38 percent after the televised clash.

And Trump's share of the vote moved up from 44 percent to 45 percent, despite Harris and her supporters claiming victory. 

The two candidates met for the first time in the ABC News debate in Philadelphia. They spent more than an hour and a half tussling over abortion, the economy and foreign policy.

Harris came with a plan to knock Trump off his stride and appeared to succeed. She generated the most viral moment of the night when she ridiculed Trump's rallies, saying that people left early out of 'exhaustion and boredom.'

He defended what he called the 'most incredible rallies in the history of politics' before pivoting to repeat an extraordinary online rumor about migrants eating pets.

'Talk about extreme,' Harris said, laughing. 

Trump again refused to acknowledge his 2020 election defeat and at times raised his voice as he launched personal attacks at Harris. 

The result was that in our poll independent viewers said she came across as the more presidential, beating Trump by 49 percent to 43.

And he was seen as by far the most aggressive, at 64 points to 25.

Yet, he performed just as well on some of his key issues as he did in June, when he flummoxed President Joe Biden. 

Viewers thought he did better on the economy, the border, foreign affairs, and Israel, and tied with Harris on tax. She won on abortion, healthcare and democracy. 

It was his temperament and style that let him down. Viewers said Harris appeared more competent, mentally astute, on top of detail, most genuine, most joyful, and the candidate that most represented change.

Trump was judged weakest and most annoying but also funniest. 

James Johnson, co-founder of J.L. Partners who conducted the poll, said independents hold the keys to the White House and had given Harris the win on the night. 

But it might still take time to filter into headline poll numbers as both sides try to spin the night their way and control the media narrative. 

'This wasn't a knockout blow. The poll suggests her performance still left Americans in the dark about the content of her plans,' said Johnson.

'And on the issues, Trump led on the same areas he did with Biden in June, such as the economy, foreign affairs, and the border.

'But she hit all her lines, she twisted Trump in knots, and she led the subject away from her weakest areas.' 

In particular she was able to portray Trump as aggressive and rude, he added. 

'For all their support for Trump on the issues, independents balk at his temperament,' said Johnson.

'We will have to wait for the next polls to see the effect this had had electorally—and to work out whether this is priced into voters' views of Trump already or not.'

Both sides deployed surrogates to claim victory in the spin room filled with journalists afterwards. 

'It was the best debate personally I've ever had,' said Trump.

The Harris campaign quickly asked for a second debate in a sign of their confidence.

'Under the bright lights, the American people got to see the choice they will face this fall at the ballot box: Between moving forward with Kamala Harris, or going backwards with Trump,' said Jen O’Malley Dillon, campaign chair.

The clash came with high stakes for both sides. 

Trump has struggled to find momentum since Harris entered the race, but the Democratic nominee has also seen her honeymoon—with huge fundraising numbers—fade during the past week.

The result is an election on a knife-edge.

The DailyMail.com/J.L. Partners election model gives Trump a slight edge, with a 55 percent chance of victory.