Donald Trump is just six Senate votes from impeachment, according to an analyst at a prominent independent think-tank.

Support for the President among Republican Senators has waned to the extent that Mr Trump is likely to only hang onto his seat by six votes, according to Elaine Kamarck of the Washington-based research group The Brookings Institution.

Ms Kamarck, who is director of the Centre for Effective Public Management, said 12 Republican Senators had "no fear of the President" and had indicated they could vote against him in a vote.

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Among the Senators likely to rebel was John McCain, who delivered the killer blow to Mr Trump's replacement for Obamacare, Ms Kamarck said in an article on the think-tank's website.

The US constitution allows Congress to remove a president before they have completed their term if enough members vote to say they committed "treason, bribery, or other high crimes and

misdemeanours".

An article of impeachment must get a majority vote in the House of Representatives before reaching the Senate. Once there, at least two-thirds of senators must find the President guilty for him to be removed.

Ms Kamarck said that 12 rebellious Republican Senators combined with 48 Democrats "who have shown no inclination to work with this President" meant Mr Trump was six votes away from a Senate conviction.

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