Blaine subsequently secured Manley's appointment as Augusta's U.S. postmaster (an important federal post under the then-existing spoils system).
Manley subsequently became Blaine's right-hand man on the Maine Republican State Committee, on which he served 1881–1900, and which he chaired for 15 of those years.
In 1894, then-NRC Chairman Thomas Henry Carter resigned the Executive Committee Chairmanship in favor of Manley, while retaining nominal control of the NRC.
This set the stage for Manley to personally manage the 1896 presidential candidacy of Thomas Brackett Reed, who was defeated for the Republican nomination by William McKinley.
McKinley's victory in the convention gave Mark Hanna control of the NRC, though Manley stayed on to run the party's New York headquarters, serving as Secretary of the National Committee and chairing various sub-committees until 1900.