1972 United States Senate election in Illinois

The 1972 United States Senate election in Illinois took place on November 7, 1972. Incumbent Republican United States Senator Charles H. Percy sought re-election to the United States Senate. Percy was opposed by Democratic nominee Roman Pucinski, a United States Congressman from Illinois's 11th congressional district, whom he was able to defeat handily to win a second term. As of 2022, this was the last time a Republican was elected to the U.S. Senate from Illinois during a presidential election year, the last time an Illinois Republican won a Senate election by double digits, and the last time any candidate has swept every county in the state. This election was the fourth consecutive time in which a United States Senate election in Illinois took place two years after a previous United States Senate election in Illinois after 1966, 1968 and 1970.