He ran for governor in 1876 against Democratic opponent Francis T. Nicholls, and at the end of the election both candidates claimed victory, leaving the matter to be resolved by President Rutherford B. Hayes.

He left the law office in 1861 to join the Twelfth Maine Volunteers as first lieutenant and was promoted to captain of Company B.

The regiment was assigned to General B. F. Butler's Division, participating in the Louisiana campaign and the captures of New Orleans and Port Hudson.

After the close of the war Captain Packard settled in New Orleans, engaged in the practice of law and in 1867 was elected delegate to the Constitutional Convention and was made chairman of the Board of Registration consisting of seven men who were charged with the duty of administering the civil affairs of the State from the adjournment in April until the inauguration of the State Government in July, 1868.

As delegate to the Republican National Convention in 1876, he supported Blaine after it was seen to be impossible to nominate General Grant.