Donald Trump narrowly trailing Hillary Clinton by three points in latest US election poll

The margin of victory has become increasingly narrow

The same poll last week gave Ms Clinton a five-point lead (Reuters)

In a blow to Hillary Clinton’s campaign, her lead over Donald Trump has fallen to just three points nationwide.

Ms Clinton is forecast to gain 47 per cent of the vote over Mr Trump's 44 per cent, according to a new poll from NBC News/Survey Monkey.

In the same poll last week, Ms Clinton had a wider gap of 48 per cent to his 43 per cent.

The news comes after FBI director James Comey and the Justice Department decided not to pursue Ms Clinton for criminal charges although they determined she had been “extremely careless” regarding the misuse of her personal email server as secretary of state.

Attorney General Loretta Lynch, testifying on Tuesday about the email scandal, said she “accepted the FBI findings” but defended the Justice Department’s ruling.

A total of 82 per cent believe that the misuse of emails was “not appropriate”, compared to just 15 per cent who say it was.

Around two thirds of those surveyed believe that the Democrat is neither safe nor trustworthy.

Despite the flagging poll results for Ms Clinton, Mr Trump is still viewed unfavorably by the majority of the electorate - 62 per cent - in the new poll. But his unpopularity rating is just 2 per cent higher than Ms Clinton.

The new poll sampled 7,869 adult registered voters between 4 and 10 July.

According to a different poll from RealClearPolitics, Ms Clinton has a five-point lead nationwide over Mr Trump.