Morton was born in Vermont, the son of a minister. He worked as a clerk in a general store in Enfield, Massachusetts, taught school in Boscawen, New Hampshire, and eventually got into business in New York City, first in dry-goods and leter in banking. Morton was elected, as a Republican, to the 46th and 47th Congresses. In 1880 he was asked by President James Garfield to be his vice presidential running mate, but Morton declined the offer. If he had accepted and history continued on the same course, Morton would have become the 21st President, instead of Chester A. Arthur, after Garfield's assassination.
Garfield appointed Morton as the United States Minister (Ambassador) to France from 1881 to 1885. Coincidentally, Charles J. Guiteau reportedly decided to murder Garfield because Garfield would not make him minister to France.
Morton was elected Vice President of the United States in 1888 on the Republican ticket with President Benjamin Harrison, but he wasn't much of an asset to his President. Harrison tried to pass the Lodge Bill, an election law enforcing the voting rights of freed slaves in the South, but Morton did nothing to protect the bill from a Democratic filibuster in the Senate. Harrison blamed Morton for the bill's eventual failure, and, at the Republican convention prior to the 1892 election, Morton was replaced by Whitelaw Reid as the vice-presidential candidate. Harrison and Reid went on to lose the 1892 election, to Grover Cleveland and Adlai E. Stevenson.
Morton went on to serve as Governor of New York in 1895 and 1896. He was considered for the Republican nomination for the presidency in 1896, but the Republican Party chose William McKinley instead. After his public career was over, he became a real-estate investor.
He died at Rhinebeck, in Dutchess County, New York, on his 96th birthday, the only Vice President to have died on his birthday. Morton was the second longest-lived Vice President. Only John Nance Garner lived longer. Morton survived five of his successors in the vice presidency: Adlai E. Stevenson, Garret A. Hobart, Theodore Roosevelt, Charles W. Fairbanks and James S. Sherman.