Though the boundaries of Copeland constituency have changed numerous times, it has been a Labour stronghold since 1935.
But although the party has won the seat at every election for the last 80 years, it has not always had a comfortable majority.
The current constituency boundaries were drawn up in 2010, when Labour's Jamie Reed won the seat. He had also polled highest in 2005 under the previous boundary arrangements.
This year, he will compete against candidates from the Conservative Party, the Green Party, UKIP, and the Liberal Democrats to try to keep the seat.
Geographically, the Copeland constituency stretches from Cumbria's west coast to the western fells.
It includes the towns of Whitehaven, Egremont, and Millom to the south, and Keswick to the east.
At the last election the breakdown of results was as follows:
So, what issues are important to voters in the constituency?
At a glance:
- Energy plays a huge role in the local economy - both nuclear, and renewable
- Healthcare and the NHS remain a key concern
- Sellafield is the constituency's biggest single employer. It has a workforce of more than 10,000, and the average wage is £60,000
- Tourism is the main industry in Keswick, and the average house price there is £282,000
For some voters, the price of housing is an important issue:
The NHS is the top priority for some voters:
Others claim more needs to be done to improve the area for residents with disabilities.
As things stand, they believe parts of the constituency are inaccessible:
We asked some of the candidates standing for election on May 7 to tell us what it is that they think matters in the constituency:
A full list of parliamentary candidates standing for election in the Copeland constituency is as follows:
- Danny Gallagher (Liberal Democrats)
- Stephen Haraldsen (Conservative)
- Michael Pye (UKIP)
- Jamie Reed (Labour)
- Allan Todd (Green Party)
Watch Katie Hunter's full report on the Copeland constituency: