Join us live as Donald Trump and Hillary Clinton battle it out again in the second 2016 presidential debate.

A third debate will be held on October 20 and the US election will take place November 9 New Zealand time.

It is hard not to get the impression from press assessments and social media that the two major political parties in the US and political analysts are already pitching ahead to the post-Trump era.

Dozens of Republican worthies appear to have got a glimpse of writing on a very big wall and have jumped at Trump's latest scandal to flee while there's still time. Never-mind all the previous out-clauses they could have tripped-over Mexicans, Muslims and insults to women.


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Think-pieces about what impact Trump will have on Republican candidates for the NEXT presidential election have already appeared. So have articles on Democrat tactics towards Congressional races and the question of what if Republicans decide to disrupt President Clinton II's programme.

Yet we have a month to go until the big day - is it effectively the end already?

Steve Schmidt, a Republican strategist, is one expert on record before today's debate as saying "It's over".

The reason why many pundits have come to the same conclusion is that the Republican nominee's problems have been building like a matryoshka doll.

The most obvious crippling blow to the Trump campaign came at the weekend when a tape surfaced of the businessman boasting of using his fame to make sexual advances to women.

But Trump had been visibly floundering since Democrat Hillary Clinton took him apart in the first debate on September 27.

His performance and subsequent row with a former Miss Universe, piled on perceptions that he lacked the temperament to rule.

Now Clinton is back out to the about 4 percentage point national poll average lead she has held most of the year.

Her standings in important battleground states are about where they were during her post-Democratic Convention bounce in August. Her leads today on include Pennsylvania +8.6, Colorado +7.3, Virginia +7, Michigan +7, Wisconsin +6.3. That's an impressive firewall.

Trump's advantage in Ohio has fallen from +1.6 yesterday to +0.5 today.

Should those margins stay steady Trump simply cannot find a way to a winning 270 Electoral College votes. If the election were held today, RCP says Clinton would win with 340 to Trump's 198. Trump's problem has always been not being able to draw enough voters beyond his base.

The question is whether the final stages of the election resembles the 2008 election map between Barack Obama and John McCain. The Republican pulled ahead in September but the Democrat ran away convincingly in October.

There's always the chance of an October surprise upsetting Clinton but so far the surprises have been a chocolate box assortment - with so many Trump crunchie bars, the occasional Clinton caramel can slip by. An info dump on her Wall Street speeches last week was pretty much lost in the Trump noise.

Clinton's key task in today's debate will be to do no harm to her front-running status. Trump has to somehow shake it up, but avoid being baited.

He was most effective in the first debate near the start when he stressed economic pain and accused Clinton of doing nothing during her years as a public servant.

How the candidates deal with the latest revelations and whether Trump raises former President Bill Clinton's past will be either fascinating or mark a new low (or both). The tricky part will be raising such subjects within the format of the debate.

Unlike the first debate where the candidates worked with a single moderator, this time there are two, and also questions from people in the audience to deal with. The candidates can sit or move around.

Will Trump "go nuclear" as one ally yesterday suggested he should? And would it work?