Trump's approval rating has fallen in every single state since he became President

In less than one year as President, Donald Trump has become less popular in every single US state, a new poll shows.

Morning Consult surveyed more than 470,000 Americans between the months of January and September about their opinions on Mr Trump. The pollsters found that the President's approval rating had dropped in every state – including those that supported him in the election – in the eight months since his inauguration.

In fact, Mr Trump’s approval rating dropped by double digits in several of the states he won easily in November, including Tennessee, Mississippi, Kentucky, Indiana, and Kansas. He saw a slightly less dramatic decline in states where he scored narrow victories, such as Michigan and Pennsylvania.

Overall, his approval rating was down six points, from 49 per cent in January to 43 per cent in September. His disapproval rating, meanwhile, increased by 13 per cent.

In 25 states and the District of Columbia, the majority of voters said they disapproved of Mr Trump’s job performance in September.

The drop-off could be due to any number of factors, from the President’s ongoing disputes with members of his own party to the mounting investigations into his possible collusion with Russia. The GOP’s failed attempts to repeal and replace Obamacare also led to drops in Mr Trump's approval rating, as did his controversial response to a white supremacist rally in Charlottesville.

Much of the popularity decline comes from Democrats, who have failed to warm up to the Republican leader. But his approval rating among independents – a crucial demographic in his November victory – has also plummeted, from a fifty-fifty split to -18.

Republican strongholds like Wyoming, West Virginia, and Alabama still support the President by double-digit margins. But the pollsters note what they call an “enthusiasm gap” among Republicans: The share of GOP voters who strongly approve of Mr Trump declined by 10 points from January to September.

The gap may be troubling to members of Mr Trump's party, who are trying to keep a Republican Congressional majority in 2018. Eight Republican Senate seats are up for election in 2018, and the President's unpopularity could turn voters against them.

In fact, Democrats in the Senate have already started talking about the possibility of winning back the majority next year, according to Politico.

“The map feels a little different today than it did a few weeks ago,” Democratic Senator Chris Murphy recently told the outlet. “We might be playing a little more offence.”