Loftus was returned for county Wexford on his father’s interest, as one of a squad of ten returned by him to the Irish parliament. Lord Ely was induced to support the Union with the aid of an Irish marquessate, a United Kingdom barony and £45,000 compensation for the loss of his six pocket boroughs, which left him with the nomination of three Members at most; and, on his surrendering a pension, a seat at the Irish treasury board for his son, who was also admitted to the Irish privy council. Had his father given security for him, he might have continued as teller of the exchequer (£860 p.a.).
At Westminster, Loftus was an inconspicuous supporter of Addington’s and Pitt’s administrations. He went to France in 1802 and, though back in England, did not vote on the inquiry into the Prince of Wales’s debts, 4 Mar. 1803. Mrs Nicholson Calvert remarked of him in 1805 that he was ‘a little squat ugly man, who fancies himself like the Prince of Wales, and dresses at him. He really accomplishes making himself a frightful caricature of his Royal Highness.’
The Grenville ministry deprived Loftus of his treasury place since he had shown no disposition towards them, and he succeeded to the title soon afterwards. As ‘a leading person in the Orange interest’, he soon clashed with them, particularly when they thwarted his nomination of a successor to his county seat, regarding what he termed government hostility as an unhandsome reward for his family’s past support.