As is noted in the thread linked to in the previous post, the two March titles are generally considered to refer to different places.
It's not a current example, but there were two Earldoms of Leicester between 1837 and 1855: one held by the 3rd Marquess Townshend (created 1784, extinct 1855), and one by the Cokes (created 1837, extant).
In addition, the titles of the Marquess of Downshire and the Viscount Downe both refer to County Down in Northern Ireland.