The Crosby by-election took place against an almost unprecedented backdrop of division and disunity within both the Conservative and Labour parties, combined with social unrest and economic recession in the United Kingdom as a whole.

It expounded left-wing policies, with perceived weak leadership provided by Michael Foot, who was routinely ridiculed by the national press.

Prime Minister Margaret Thatcher had recently sacked or neutralised the remaining allies of Edward Heath, the previous more moderate Conservative leader, and the country was being subjected to the full rigours of monetarism, her economic policy.

The Catholicism of the area could be ascribed to two factors: those of Liverpool-Irish ancestry whose families had migrated the six miles north from the city-centre over the previous century to become the middle-class intelligentsia, doctors, lawyers and the like; and a significant indigenous group who traced their roots to the village of Little Crosby, one of the oldest extant Catholic villages in England.

[1] For the by-election, the Conservatives stood John Butcher, a chartered accountant and a Royal Navy reservist, living in Cheshire and working in Warrington.

"[5] The victorious Pitt claimed that the Alliance had "caught the imagination of the voters" and that as consequence there were "no longer any safe seats for Tory or Labour in the country."

The political editor of The Glasgow Herald, Geoffrey Parkhouse, said the Croydon result "shattered" both Labour and the Conservative leadership who would fear Pitt's prediction.

[2] John Desmond Lewis, a 22-year-old student from Hayes in Greater London,[6] contested the election as the President of the Cambridge University Raving Loony Society.

[2] John Kennedy stood to highlight the case of seven students at Middlesex Polytechnic who had been suspended after a sit-in protest demanding nursery facilities,[7] while Donald Potter, a former Young Conservative and founder of the "Close Encounters" lonely heart group, stood to promote his idea of a national phone line for lonely people.

Jenkins won another seat for the SDP at the Glasgow Hillhead by-election in 1982, but the party suffered setbacks at the 1983 general election, and Williams lost Crosby to a new Conservative candidate aided by the fact that boundary changes had been implemented bringing Aintree into the constituency in place of Waterloo and Seaforth (which transferred to Bootle Constituency).