Dennis Ray Rehberg is an American politician and member of the Republican Party. He served as the lieutenant governor of Montana from 1991 to 1997 and as the U.S. representative for Montana's at-large congressional district from 2001 to 2013. Rehberg was the Republican nominee for the United States Senate in 1996 and 2012, losing to Democratic incumbents Max Baucus 50% to 45% and Jon Tester 49% to 45%, respectively. He subsequently became a co-chairman at Mercury, a Washington D.C. lobbying firm.

From 1993 to 2023, Montana was represented in the United States House of Representatives by one at-large congressional district, among the 435 in the United States Congress. The district was the most populous U.S. congressional district, with just over 1 million constituents. It was also the second-largest by land area, after Alaska's at-large congressional district, and the largest by land area in the contiguous United States.