A series of moves by Donald Trump’s administration to sow doubt in the integrity of US elections have intensified concern among voting experts – and sparked hope among election deniers – that it could declare a national emergency. The White House and US federal agencies have released a string of documents this summer – including disputed analyses of alleged voting by noncitzens and historical intelligence memos – stoking expectations that the US president could move to exert greater control over November’s US midterm elections. Trump used a primetime television address in July to claim – again – that US elections...