Chester Arthur
Chester Arthur was a cog in the ill-famed corrupt New York political machine. He was a notorious supporter and beneficiary of the “spoils system”. His entire career, he awarded government jobs to his party members. Before becoming Vice President, he was head of the New York custom-house, a symbol of waste, fraud, and ineptitude among federal offices. He was nominated because he was a stooge of the leader of the New York machine, who was too notoriously corrupt himself to be electable.
When he became president after the assassination of James Garfield in 1881, he shocked everyone (including his friends and supporters) by refusing to make the corrupt appointments his party demanded. To the surprise of reformers, Arthur took up the cause of reform, though it had once led to his expulsion from office. He was praised for his veto of a ‘Rivers and Harbors Act’ that would have appropriated federal funds in a manner he thought excessive. He pushed the Pendleton Act through Congress, establishing a federal civil service based on merit.
In short, politician breaks promises he made to get elected and gets admired for it.