Ian Bruce was first returned for this constituency in 1987 and went into the last election with a notional majority of 12,617. However, Labour slashed the Conservative margin to 77. The Referendum Party received 2,791 votes, saving its deposit, and UKIP polled a further 861 votes.
Labour rose from third place with a 15% increase in its share of the vote, but this was not the party's best-ever result in this constituency. On one occasion the seat was briefly Labour after a Eurosceptic independent ran against the official Conservative in a by-election in 1962.
South Dorset is centred on the seaside resort of Weymouth and the Isle of Purbeck, and reaches as far as Swanage to the east. The seat's heritage coastline offers many peculiarities - stacks, arches, spits and bars, and the majestic Lulworth Cove.
There is also the on-shore oil field at Wytch Farm and the Portland stone and Purbeck marble quarries. Indeed, stone from Portland has gone to build most of this country's cathedrals.
Other points of interest are the Bovington Tank Museum, Lawrence of Arabia's old house at Cloud's Hill, Corfe Castle and many features associated with the novels of Thomas Hardy.