Born in Ithaca, New York, he attended the common schools and moved to Galena, Illinois, in 1836, to Fort Snelling, Minnesota, in 1838, and to Burlington, Iowa, in 1843, where he engaged in mercantile pursuits.
He was elected mayor of Burlington in 1863 and as a member of the Iowa House of Representatives from 1871 to 1877, serving as Speaker for two terms.
He was an unsuccessful candidate for reelection in 1890, but was appointed by President Benjamin Harrison as Assistant Secretary of the Treasury, serving from 1892 to 1893.
In 1894, Gear was elected by the Iowa General Assembly to the United States Senate.
He had been chairman of the United States Senate Committee on Pacific Railroads in the Fifty-fourth through Fifty-Sixth Congresses.