Welcome to the inquiry on the BBC World Service.

Each week, one question, four expert witnesses and an answer.

Everything looks good for the US Democratic presidential nominee Joe Biden

with less than a week to go until election day, some national polls suggest he's 8% or more ahead.

But Biden's own campaign manager has privately warned these figures may be inflated.

The race is much closer than the polls

indicate and President Trump could still win. The Democrats are still

scarred by what happened in 2016.

Then the pollsters and forecasters said Hillary Clinton would beat Donald Trump.

Clinton did win the popular vote, but because of the US electoral system, she lost the election.

Will history repeat itself?

In this week's inquiry, ask can President Trump still win.

Part one. Part 1, The Polster.

My name is Sean Trendy.

I'm the Senior Elections analyst for Real Clear Politics.

Our first expert witness's job is to analyze the polls. He thinks that the

presidential race is likely to be closer than Trump's eight or nine point national poll lag suggests.

When you look at the state level polling, it's a little bit more optimistic for President

Trump.

He's down by about probably six or seven points in the

state that would get him Electoral College vote number 270 which would allow him

to win. The point here is that it's the number of electoral college votes a

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