the Conservatives' vote share remains the largest gained in any post-war election by any government (47/48% IIRC).
Very special circumstances. Voters still remembered vividly 45 to 51, under Labour, the post-war debt state, exaggerated by the appalling 47 winter. rationing of virtually everything. Churchill came in, Festival of Britain, rationing was phased out. Post war gloom was monochrome, Conservative 50s Britain was Technicolour. Media were very gentle to politicians. An easy sell for the candidates.