[3] Going against the general opinion of the Democratic Party, he was a strong advocate of the Wilmot Proviso, which would have restricted the spread of slavery to new states.

He was active in supporting his friend Lewis Cass's unsuccessful run for president in 1848 and did not seek reelection in that year.

[1] Following the inauguration of James Buchanan in 1857, McClelland retired from public office and began a private law practice in Detroit.

[3] His former residence at 47 East Elm Avenue in Monroe, Michigan, was listed on the National Register of Historic Places in 1971 as the Governor Robert McClelland House, and is today privately owned.

[4][5] This article incorporates public domain material from the Biographical Directory of the United States Congress