One of the railroad officials who controlled Crédit Mobilier was also a congressman, Oakes Ames of Massachusetts. He offered some of his colleagues the opportunity to buy Crédit Mobilier stock at par value, well below what it sold for on the market, and the railroad got its additional appropriations.[112]

Editorial cartoon: Uncle Sam directs U.S. Senators and Representatives implicated in the Crédit Mobilier scheme to commit Hara-Kiri.
The story broke in July 1872, in the middle of the presidential campaign. Among those named were Vice President Schuyler Colfax, Massachusetts Senator Henry Wilson (the Republican candidate for vice president), Speaker James G. Blaine of Maine, and Garfield. Greeley had little luck taking advantage of the scandal. When Congress reconvened after the election, Blaine, seeking to clear his name, demanded a House investigation. Evidence before the special committee exonerated Blaine. Garfield had said in September 1872 that Ames had offered him stock but he had repeatedly refused it. Testifying before the committee in January, Ames said he had offered Garfield ten shares of stock at par value, but that Garfield had never taken them or paid for them, though a year passed, from 1867 to 1868, before Garfield had finally refused. 