He was born in Long Branch, New Jersey to Sophia Vanderveer and Addison Willard Hobart, a descendant in the eighth generation of English immigrant to Massachusetts. Edmund Hobart (1573-1646), and grew up in Marlboro Township. He graduated from Rutgers College in 1863 and was a member of The Delta Phi Fraternity. He was admitted to the bar, and practiced in Paterson.
Hobart served in the Paterson city council in 1871 before serving in the New Jersey General Assembly from 1872 to 1876, serving as speaker in 1874. He was a member of the New Jersey Senate from 1876 to 1882, serving as its president in 1881. He represented Passaic County.
In addition, he served in various positions in the Republican Party: chairman of the New Jersey Republican State Committee, 1880–1891, and the New Jersey member of the Republican National Committee, 1884–1896. He also failed in his bid for the United States Senate in 1884.
Hobart was twice offered, but declined, the Republican nomination for Governor of New Jersey in 1892 and 1895.
Hobart was also a prominent and successful businessman and industrialist, who accumulated a large fortune.
He was nominated as the Republican candidate for Vice President on the ticket with William McKinley, and was elected in the 1896 presidential election.
He served as Vice President from March 4, 1897 until his death from heart failure in Paterson, New Jersey on November 21, 1899, aged 55.
During his tenure Hobart became one of the McKinleys' friends and his close confidant and adviser. He was called "Assistant to the President". Because of this and in contrast to the tradition of a powerless Vice Presidency, he is regarded as one of the most powerful Vice Presidents while in office.
In 1899, Hobart became ill. He returned to New Jersey to recover, but instead became worse. He died from heart failure. Following his death, the Vice Presidency remained vacant for more than a year until the inauguration of Theodore Roosevelt to that post in 1901. Hobart is interred in Cedar Lawn Cemetery.
The city of Paterson placed a bronze statue of Hobart in front of its city hall, next to a statue of Alexander Hamilton.
Hobart married Esther Jane "Jennie" Tuttle on July 21, 1869.
During his tenure as Vice President, his wife frequently performed the duties of First Lady because Ida Saxton McKinley, wife of President of the United States William McKinley, suffered from epilepsy.
New Jersey United States Senate election, 1884 (by state legislature):
1896 Republican National Convention (Vice Presidential tally):
United States presidential election, 1896
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