Decreasing differences between winner and runner-up vote share
1951 LSE – Winner (44.99%) | Runner-up (3.29%)
1957 LSE – Winner (47.78%) | Runner-up (8.92%)
1962 LSE – Winner (44.72%) | Runner-up (9.94%)
1967 LSE – Winner (40.78%) | Runner-up (8.67%)
1971 LSE – Winner (43.68%) | Runner-up (5.12%)
1977 LSE – Winner (41.32%) | Runner-up (34.52%)
1980 LSE – Winner (42.69%) | Runner-up (9.39%)
1984 LSE – Winner (48.12%) | Runner-up (5.71%)
1989 LSE – Winner (39.53%) | Runner-up (17.79%)
1991 LSE – Winner (36.4%) | Runner-up (20.07%)
1996 LSE – Winner (28.8%) | Runner-up (20.29%)
1998 LSE – Winner (25.82%) | Runner-up (25.59%)
1999 LSE – Winner (28.3%) | Runner-up (23.75%)
2004 LSE – Winner (26.53%) | Runner-up (22.16%)
2009 LSE – Winner (28.55%) | Runner-up (18.8%)
2014 LSE – Winner (31.34%) | Runner-up (19.52%)
2019 LSE – Winner (37.7%) | Runner-up (19.67%)