 He was an unsuccessful candidate for judge of the court of common pleas in 1899.Rothermel was elected as a Democrat to the Sixtieth and to the three succeeding Congresses.He served as the chairman of the United States House Committee on Expenditures in the Department of Commerce and Labor during the Sixty-second Congress, and of the United States House Committee on Expenditures in the Department of Commerce during the Sixty-third Congress.