Underwood's 1956 election as Governor of West Virginia marked the first election of a Republican to the office since 1928. He had defeated Charleston Mayor John T. Copenhaver by only 7,200 votes in the primary, and had made a decisive victory against Democratic U.S. Representative Robert Mollohan in the general election by 63,000 votes. Only a week prior to the election, it was discovered that Mollohan had received $20,000 and two cars from a coal operator on a strip mine at a male reformatory in Pruntytown while Mollohan was superintendent of the institution. Underwood had turned 34 years old only one day before the election, making him one of the youngest U.S. governors to have ever been elected.