In the 66th United States Congress through 68th United States Congress, Lehlbach served as the chairman of the Committee on Reform in the Civil Service. In 1924, Lehlbach was a delegate at the Republican National Convention. He later served as chairman for the Committee on Civil Service in the 69th United States Congress through 71st United States Congress. After serving 18 years as the representative of the 10th district, Lehlbach was moved to New Jersey's 12th congressional district. In the 1936 House election, Lehlbach was up for re-election against Democrat Frank W. Towey, Jr. In a heated battle, Lehlbach lost his election bid by capturing 49.6% of the vote in comparison to Towey's 49.9%.