From 1918 to 1950 Seaforth was within the Parliamentary constituency known as Waterloo, a safe seat for the Conservative Party, and then until 2010 within the Crosby constituency, whose MP from 1997 to 2010 was Claire Curtis-Thomas, of the Labour Party. Prior to her election the Crosby seat was generally considered a Conservative Party stronghold, like its predecessor seat, with Tory MPs elected at every election, except for the 1981 Crosby by-election, when Shirley Williams of the Social Democratic Party was elected. As a result of boundary revisions for the 2010 general election, the Crosby constituency was abolished and Seaforth was included in the expanded Bootle constituency, represented by the Labour MP Joe Benton.