He serving as Private in Union Army from 1862 until the end the American Civil War,[2] enlisted in the One Hundred and Twenty-eighth Regiment, Ohio Volunteer Infantry.

When Alexander moved to Fort Wayne, Indiana in 1870, he was one of the editors and proprietors of the Daily Gazette from 1871 to 1874, and a delegate to the Republican National Convention at Philadelphia in 1872.

In 1896, Alexander was elected as a Republican to the 55th Congress as a United States representative for New York's thirty-third district, where he served seven terms.

It focused on prominent political leaders such as Grover Cleveland, Thomas C. Platt, and Theodore Roosevelt.

Alexander died on January 30, 1925, in Buffalo, New York; and was buried at the Forest Lawn Cemetery there.