Soon after the State Convention he published a letter in the Albany Journal, in which he repudiated theprinciple of the unit rule, and declared for Mr. Blaine. The letter attracted attention throughout the country and gave its author great prominence in the opposition to the " third term movement." It is generally conceded that it was his leadership and organizing ability, more than that of any other man, that broke the power of the " unit rule " in Republican conventions, and defeated the "third term" candidate.

In March, 1881, Mr. Robertson was nominated by President Garfield for collector of the port of New York. His political acts having been distasteful to the Senators from this State, they demanded the withdrawal of his nomination by the President. This being refused, a bitter contest followed, which was ended by the resignation of the Senators in May, and the confirmation of Mr. Robertson soon afterward. He did not, however, assume the collectorship until the 1st of August, as the Legislature (he being in the Senate) did not adjourn till late in July. His judicial and legislative experience had prepared him for the most difficult duly of the position, the consideration aud decision of intricate points of revenue law, and he discharged its obligations to the satisfaction of the importers, and with the almost universal commendation of the public press.

Mr. Robertson has been conspicuous and influential in local and State Conventions for many years, took an active part in the National Conventions of 1864, 1876, 1880 and 1884, and was for fifteen years a member of the Republican State Committee. In his political life he has been remarkably successful, having never been defeated when a candidate before the people, although his principal canvasses have been made in a district of which the party majority was against him.