He contested the 1977 Birmingham Ladywood by-election for the Conservatives. The by-election, caused by the resignation of Brian Walden, was won by Labour's John Sever with a majority of 3,825. He was elected to the House of Commons ten years later at the 1987 General Election for the safe Conservative seat of Stamford and Spalding on the retirement of the sitting MP, Kenneth Lewis. Davies held the seat with a majority of 13,991 votes. The constituency was abolished in 1997, and he represented the redrawn seat of Grantham and Stamford until his retirement from the House of Commons at the 2010 General Election.