Donald Trump’s hectoring, manic and forceful demeanour was on full display during the first US presidential debate, but his attacks failed to unsettle a sure-footed Hillary Clinton who was able to deflect the challenges to her record.

Around 100 million people were expected to watch the contest, which was an opportunity for both nominees pitch their message to undecided voters.

Ms Clinton often put Donald Trump on the defensive, saying he had “rooted for” the collapse of the housing industry and had considered climate change to be a hoax.

Mr Trump repeatedly underscored his role as a political outsider, questioning the economic stewardship of President Barack Obama and the administration of former President Bill Clinton, who sat in the front row.

But while Ms Clinton handled the tricky questions and the constant interruptions to her answers, analysts said that, like her opponent, she may not have done enough to convince voters to switch camps.

So, who won? We asked three experts in US politics.

Jesse Barker Gale
Congressional Fellow in the United States House of Representatives and a visiting research scholar in the School of Foreign Service at Georgetown University

The debate was good for Clinton. Trump seemed on point and focussed in the first 15 minutes but the last 75 minutes he was incoherent. Trump was easily led by Clinton. He took the bait several times whereas a more prepared candidate would have not been caught.

I didn’t see Trump broadening his constituency. The purpose of these debates is to look presidential and reach undecided voters and Trump didn’t do that. There are a lot of undecided voters in this election, but I didn’t see him making any moves to capture the sensible centre.

Trump was unprepared and didn’t offer policy specifics, as is his wont. It seems that he’s campaigning on wing and a prayer and he didn’t have the detail.

Clinton, on the other hand, did make a strong pitch to the sensible centre. She talked about delivering very good policies in policing and African-American communities. Her knowledge in foreign policy is obviously superior.

Donald Trump’s campaign played down his ability to debate and I think even those lower expectations will fail to avoid the analysis that the did a poor job of explaining his claims to being President.

It was a win to Clinton but not by knockout blow. Things may move back in her direction by three or four points.

Chas Licciardello
Co-Host of Planet America on ABC TV, member of The Chaser

To the extent that debates make a difference it’s about moments that can be used in an attack ad. That moment was when Trump failed to control himself and went on a five minute rant about his wonderful temperament.

The audience, which had been largely silent to that point, burst out laughing and he looked extremely unhinged. That was something people will remember.

Hillary was both lucky and did well. The Clinton Foundation didn’t get a mention and she did well when Trump brought up the emails. She didn’t engage at all.

No one looked more pre-planned than Hillary, but Trump was determined to harp on about the 30 years she has spent in politics – she’s an elite talker but not a doer. That’s a good attack, but then he dropped it. He came in with the right strategy but then got distracted. Clinton often let his jabs go and he never let her jabs go.

We shouldn’t forget the broader picture, Trump has caught up the best part of seven points in recent weeks. Why that is, nobody knows. I would have thought this debate might stop that momentum, but whether it will reverse it, I’m not sure.

Donald Trump and Hillary Clinton shakes hands after the debate.

James Cahill
Deputy Editor of Election Watch at the University of Melbourne

I don’t think this debate did much to help Trump’s case in expanding his supporter base beyond what it already is.

His easiest get would have been to appeal to college-educated, GOP-leaning women to vote for him, but he did nothing to win over those voters or any other people.

I actually thought Mrs Clinton might have come out and thrown some more punches, but she played – to use an Australian term – a straight bat. Only a couple of times, when he needled her, did she give a little bit of push back. She actually played a straighter bat than I expected.

Clinton looked determined to project a presidential image, whereas Trump totally came out as himself right from the get-go.

It was as though she decided she was going to let Donald do himself in, and decided to rely on post-debate coverage to make her case.

It find it hard to believe Trump’s advisors would not have counselled him to project a calmer, more measured and informed image.

Instead he constantly interrupted Clinton and at times acted like an irritated and annoyed bully. Then, when it was his turn to use the two minutes he often resorted to quoting obscure references or shifting his answers towards tangentially related issues.

Generally speaking I think he would have appealed to his existing rusted-on supporters, but would have made many undecided voters uncomfortable about the prospect of electing him president in October.