MPs' expenditure and general election campaigns: Do incumbents benefit from contacting their constituents?

Most studies of the impact of local campaign expenditure on British election results have found that expenditure by incumbents has less of an effect on the outcome than does that by challengers. Some argue that this, in part, reflects an underestimate of how much is spent by incumbents because it excludes their expenditure under various parliamentary allowances which facilitates contacts between MPs and their constituents. Data on spending under those allowances are now available and are used here to evaluate its impact at the 2005 general election in England. The analyses show that only expenditure by Conservative MPs had any impact on their re-election chances.