As a congressman, he is credited by many historians as being the single most important influence in the building of the Union Pacific portion of the transcontinental railroad.

[1][2] In his youth, he obtained a public school education and later worked in the family workshops to learn each step of the manufacturing process.

Driven by the settlement of the Midwest, by the discovery of gold in California and Australia, as well as by railroad construction, the shovel manufacturing business boomed.

In 1865, President Abraham Lincoln appealed to him to take control of the Union Pacific (UP) portion of the project, which had become mired down because of the war, and had built only 12 miles (19 km) of track.

The contracts were later transferred to the Credit Mobilier Company of America after Ames ousted its founder Thomas Durant.

[4] In 1872, it was disclosed Ames sold shares in Credit Mobilier to fellow congressmen at a price greatly below the market value of the stock.