SENATE Republicans returned to Washington in shock and disarray today after the sudden death of veteran legislator Lindsey Graham, a key ally of President Donald Trump.

The South Carolina senator, 71, died on Saturday evening after a suffering a torn aorta, according to a statement from his office on Sunday.

Trouble on the US right has been compounded by the sickness of former Republican leader Mitch McConnell, who has been in hospital for almost a month. He broke weeks of silence about his health on Sunday evening, saying that he was recovering from pneumonia and a fall at his home.

The continued absence of the Kentucky senator and the surprise death of Mr Graham have shaken Republicans who were already at odds with Mr Trump and deadlocked on several priorities as they return from a two-week break.

The reduction in their numbers in the Senate, where they held a 53-47 majority over the Democrats before Mr Graham’s death, is sure to make run-up to the November midterm elections even more difficult for the party.

Republicans have been unable to get much done as the Senate, House of Representatives and White House have disagreed on legislative priorities and as Mr Trump has criticised Senate Republicans, in particular, for not passing his legislation to require proof of citizenship for voters. Mr Graham often served as a pivotal intermediary.

“He was a great — like a gauge, a temperature gauge of the Senate,” Mr Trump told NBC’s Meet the Press on Sunday morning. “He could go in and get something approved. He would just get people on his side.”

Recent Republican troubles have included Mr Trump blocking the Senate from confirming one of his own nominees, senators’ resistance to funding parts of his White House ballroom project and the president forcing them to defend the Iran war even as they questioned the strategy and goals.

Republicans return to a number of important agenda items, including the confirmation of the president’s nominee for attorney general, Todd Blanche, and that of Jay Clayton, who Mr Trump selected to be director of national intelligence and later temporarily blocked.

Mr Graham, a congressman for more than three decades, was an enthusiastic backer of Mr Trump’s war on Iran and of Ukraine, from which he had just returned when he died.

He was once a strong critic of Mr Trump, saying before the 2016 presidential election: “If we nominate Trump, we will get destroyed … and we will deserve it.”