New Mexico Territory's at-large congressional district is an obsolete congressional district representing the New Mexico Territory, which was created in 1850. After New Mexico's admission to the Union as the 47th state by act of Congress on January 6, 1912, this district was dissolved and replaced by New Mexico's at-large congressional district.

Richard Hanson Weightman was an antebellum delegate to the United States Congress from the Territory of New Mexico. He was also a district commander of the secessionist Missouri State Guard during the American Civil War, and was killed in action at the Battle of Wilson's Creek in Missouri.