John McLean, American jurist and politician, 6th United States Postmaster General (d. 1861)
John McLean (March 11, 1785 – April 4, 1861) was an American jurist and politician who served in the United States Congress, as U.S. Postmaster General, and as a justice of the Ohio and U.S. Supreme Courts. He was often discussed for the Whig Party nominations for President.

Born in New Jersey, McLean lived in several frontier towns before settling in Ridgeville, Ohio. He founded The Western Star, a weekly newspaper, and established a law practice. He won election to the United States House of Representatives, serving from 1813 until his election to the Ohio Supreme Court in 1816. He resigned from that position to accept appointment to the administration of President James Monroe, becoming the United States Postmaster General in 1823. Under Monroe and President John Quincy Adams, McLean presided over a major expansion of the United States Postal Service. In 1829, President Andrew Jackson appointed McLean as an Associate Justice of the United States Supreme Court.

On the court, McLean became known as an opponent of slavery, and he was frequently mentioned as a presidential candidate for various parties. McLean received the support of delegates at the 1848 Whig National Convention, the 1856 Republican National Convention, and the 1860 Republican National Convention. He was one of two justices to dissent in the landmark case of Dred Scott v. Sandford. McLean served on the court until his death in 1861.