Tony Benn

Benn fought three times, in the early 1960s, to keep his Bristol South East seat after inheriting a peerage, winning a by-election he was then barred from taking and helping force the Peerage Act 1963 that let him renounce the title. Later, as MP for Chesterfield from 1984 to 2001, he held regular open surgeries and logged his constituents' problems in his diaries, which are among the best records of what an MP's casework involves. He left the Commons 'to spend more time on politics'.