Good morning, and welcome to the US politics live blog. Barely a week after sweeping to a stunning midterm victory, Democrats have found themselves facing an altogether different battle, one within their own ranks. Maryland Senator Chris Van Hollen has launched a challenge to Chuck Schumer, of New York, for the Senate’s top Democratic leadership post. Announcing his decision during an interview with MS Now last night, Van Hollen argued that last week’s midterm election results showed Americans wanted a fundamental change in Washington, and that Democrats needed new leadership in order to deliver that.

He said: We saw a huge outburst of democracy on election day – red states, blue states, purple states – and it wasn’t only a rejection of Donald Trump and his corruption, his wars and his cruelty, it was also about a call for a larger change, to take on a broken economic system that’s rigged in favour of the very wealthy against working people, and it’s fuelled by a corrupt political syst