Attlee was greatly assisted by a number of factors in his ability to make the most of the large Labour majority of 1945 to enact his legislative programme. He had, as I say, an exceptionally able cabinet. He had the plan, in the shape of the Beveridge Report. He had the vision, in the shape of a widespread desire for social reform. And he had the values, strong beliefs which had been fostered by the war effort; that we were all in it together, that everyone’s contribution was valuable and valued, and, importantly, an ethos of fairness, most obviously embodied in the rationing which prevailed both during and after the war.
The other thing greatly in his favour was that he had the ability and the experience to get things done. He served in the War Cabinet from 1940 and became Deputy Prime Minister in 1942, more or less overseeing the Home Front to leave Churchill free to oversee the military effort. To quote his Wikipedia entry “In public, Attlee was modest and unassuming; he was ineffective at public relations and lacked charisma. His strengths emerged behind the scenes, especially in committees, where his depth of knowledge, quiet demeanour,objectivity and pragmatism proved decisive. He saw himself as spokesman for the entire party and successfully kept its multiple factions in harness.”