Republicans retain control of US Senate

Republicans have retained control of the US Senate, ousting Democratic incumbents in Indiana and North Dakota and ensuring they will remain as guardians of President Donald Trump's conservative agenda for two more years.

Despite Trump's deeply polarising effect on voters, the GOP harnessed his rock-solid popularity with hard-right voters in rural, deep-red states.

They held onto seats in the South, Midwest and West and ensured at least a 50-50 Senate - enough to give Republicans control because Vice President Mike Pence as president of the Senate would tip the balance to the GOP.

Republicans paved their path to victory by defeating Democrats Joe Donnelly of Indiana and Heidi Heitkamp of North Dakota. They also held on to competitive seats in Texas, where Sen. Ted Cruz fended off Republican Beto O'Rourke, the well-financed liberal darling, and in Tennessee, where Republican Marsha Blackburn prevailed.