US Republicans open an extraordinary midterm convention in Dallas later on Wednesday betting that putting Donald Trump at the centre of their campaign can rescue a party facing grim election forecasts, despite the president's deeply negative approval ratings.
The two-day gathering, dubbed "Trumpapalooza," is designed to persuade the Republican leader's supporters that he is effectively on the ballot on 3 November, when Republicans risk losing the House of Representatives and face a fierce fight to retain the Senate.
