In 1974, Labour was elected because people were sick of the 3 day week under the Tories and thought Labour better able to control the unions. Thatcher was elected in 1979 because Labour had failed to control the unions. In 1997 new Labour was elected because people were sick of 3m unemployed and sleaze.
...In 2010 Cameron was elected because he could look straight at the camera better than the other two. Sad times indeed.