The chief interests at Grantham were in two neighbouring Whig families, the dukes of Rutland, seated at Belvoir, seven miles from the borough, and the Brownlows of Belton and Humby, also not far away. The 3rd Earl of Cardigan, whose estate at Hougham was six miles from Grantham, supported the local Tories till his death in 1732. Most of the corporation were Tories.
At a three-cornered contest in 1715 Edward Rolt, a Tory, standing on his own interest, was returned with John Heathcote, a Whig, whose father, Sir Gilbert Heathcote, owned estates in Lincolnshire. In 1722 Lord Cardigan put up a second Tory, Francis Fisher,
in the freemen
Number of voters: about 400
