Lord Onslow, seated at Clandon Park two miles from Guildford, had considerable influence in the borough, and in 1754 both Members were returned on his interest without a contest. In 1761 the Onslow interest faced a stiff opposition from George Lane Parker, and in 1766 had to yield one seat to Sir Fletcher Norton. Thomas Whateley wrote to Grenville on 31 Dec. 1766:1

Sir Fletcher Norton, who has a very large property in and near Guildford, and has been for some time cultivating an interest there, is now declared, and on the proposition of the Onslows, they will give each other no trouble, so that he and Colonel Onslow will be chosen.

On 11 Jan. 1767 Newcastle told Rockingham the story as he had heard it from George Onslow:2

The Onslows were certainly afraid of Parker, and that somebody would get in without or in opposition to them. They found they had not a majority sufficient to carry two of their own naming (this is my conjecture); there was one Mr. Martyn of the town who had several votes at his disposal; he was very willing to be for Colonel Onslow, but would insist upon Sir F. Norton for the other; and therefore they were forced to give into it.

Henceforth throughout this period one Member was always an Onslow and the other a Norton.