The principal interest in Wigtown and Whithorn belonged to the Stewarts, earls of Galloway; the Dalrymples, earls of Stair, were in control at Stranraer; New Galloway, in Kirkcudbright, was more open owing to the attainder of the Jacobite Earl of Kenmure in 1716. Perhaps because of a series of unopposed returns, the rota of presiding burghs, as laid down in the Act of Union, was not strictly adhered to. When John Dalrymple was returned at Stranraer for a by-election in 1728, the Wigtown magistrates and council alleged on petition that he should have been chosen at Wigtown, whose turn it was.1 The House gave no ruling on this, merely declaring Dalrymple to be duly elected, but a clause was added to the Act of 1734 for regulating elections in Scotland:

Whereas there have been some mistakes in the district of the boroughs of Wigtown, Whithorn, New Galloway and Stranraer in relation to their presiding at elections of members of Parliament for that district, which may occasion disputes at future elections; for remedying thereof, be it enacted that the boroughs continue to preside in the course they are now in, and that the borough of Wigtown shall preside at the election of a member to represent that district in the next Parliament.2

Till 1734 Lord Stair was able to bring in his brother and ‘favourite nephew’ successively without opposition. When, however, the Dalrymples went over to opposition in 1733, Lord Galloway put up his son James Stewart, who defeated John Dalrymple at the 1734 election. No decision was reached on Dalrymple’s petition, alleging illegal interference at Wigtown by Galloway and his son, Lord Garlies.3 When James Stewart moved to the county in 1741, he was succeeded by his brother William, then provost of Whithorn, who was himself followed by James (again) in 1747, neither being opposed by the Dalrymples.