Between 1710 and 1754 there was no contest in Oxfordshire; but the electoral peace was broken in 1754 when Sir Edward Turner and Lord Parker, supported by the Duke of Marlborough and Lords Macclesfield and Harcourt, stood on the new or Whig interest, against the Tories, Lord Wenman and Sir James Dashwood.

This was probably the most notorious county election of the century, and no expense or chicanery was spared by either side.1 Henry Pelham, ‘with the King’s consent and knowledge’, promised £7,000 towards the Whigs’ election expenses,2 and the Tories spent over £20,000—of which over £8,000 was raised by public subscription. A double return was made, and both sides petitioned.

The House of Commons took six months to determine the petitions. Henry Fox and Lord Hillsborough managed the case for the Whigs, Sir Charles Mordaunt and Sir Roger Newdigate for the Tories. Much time was spent in deciding the validity of individual votes, but in a Whig House of Commons the result was a foregone conclusion. Sir William Meredith afterwards wrote:3

39 in 40 of the judges (the Members) knew nothing of the matter, and therefore voted as they liked best. ... Nor, to this hour, can either side tell which had the majority of legal votes, nor any Member of Parliament who voted in that question give any other reason for his vote but as he stood inclined for the old or new interest of Oxfordshire.

Neither side desired to repeat such a contest. In 1760 the Duke of Marlborough reached a private agreement with the Tories by which his brother, Lord Charles Spencer, was to stand jointly with Sir James Dashwood at the next general election. ‘The chief Whigs in that county’, wrote Lord Talbot to Bute, November 1760,4 ‘are so incensed by the un-concerted conduct of the Marlborough family ... that it is probable they would prefer a Tory to Lord Charles Spencer.’ But twenty years later Spencer, when offered office by Shelburne, wrote: ‘I am not in the least hurry about it. I will only mention that there is no objection to my seat in Parliament being left open, for there is no more danger of an opposition to me in Oxfordshire than in a burgage tenure.’