Robertson throughout the State made a vigorous eflPort to place him in nomination for the Governorship, and with excellent prospects of success, until the assembling of the convention, when the name of the honored soldier and statesman, General John A. Dix, was presented, and he was chosen to head the ticket. Again, in 1879, Judge Robertson had a strong support for the nomination, but owing to the opposition of what was known as the " machine" influence in the party, he was defeated.

In February, 1880, Mr. Robertson was appointed a delegate to represent the State in the National Convention to be held in Chicago in June. A vote was passed at the State Convention, instructing its delegates to vote as a unit, the purpose being to enable the majority of the delegates to carry it en masse for General Grant. Mr. Robertson had been in Congress with Mr. Blaine, was his warm admirer and personal friend, and believed him to be the favorite of the Republicans of Westchester for the Presidential nomination. 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.