General Duncan Campbell of Lochnell (29 June 1763 – 9 April 1837)[1] was a Scottish soldier and Whig politician from Argyll.

Campbell was elected unopposed as the Member of Parliament (MP) for Ayr Burghs at a by-election in 1809.

[6] The 1809 vacancy had been caused by the death aged 39 of the previous MP John Campbell of Shawfield and Islay, and Whig leaders had taken the opportunity to press Argyll to support a candidate of their choice.

The Earl of Lauderdale proposed Sir William Cunynghame, 4th Baronet, but Argyll preferred a clansman, even though Duncan Campbell was not a close relative.

[2] Nonetheless, when Argyll was persuaded at the 1818 general election to support Bute's candidate Thomas Francis Kennedy, Campbell stood aside in the Ayr Burghs, but did not retire voluntarily.