In 1934 McKeough won the Democratic nomination for Congress from Illinois' 2nd District. He was endorsed by the Cook County Democratic Party and its chairman Patrick Nash.[1] McKeough served four two-year terms in this position.
In 1942, McKeough, already well-known statewide, decided to run for the United States Senate. His opponent in the Democratic primary was Paul Douglas, an economist and professor at the University of Chicago who had long been associated with "reform" politics. Douglas carried 99 of Illinois' 102 counties, but McKeough's Chicago-area majority was sufficient to overcome this and win the nomination. In November, however, McKeough lost to the incumbentRepublican senator, Charles W. Brooks.
Soon after the end of his Congressional service, McKeough went to work for the Office of Price Administration, a World War II-era federal agency charged with the enforcement of wartime wage and price controls instituted to prevent inflation. He worked for this agency until January 1944. In October 1945, he was named to the United States Maritime Commission, serving on this body until 1950. He then served on the U.S. International Claims Commission from 1951 to 1953. In 1956, he worked briefly with the Great American Oil Company.
On December 3, 1956, McKeough embarked on what became his last stint in public service, as an assistant state's attorney. He held this position for exactly four years, retiring on December 3, 1960. After this, he engaged in the insurance business prior to his death in Blue Island, Illinois in 1979.[2]
He was buried at Saint Mary Catholic Cemetery in Evergreen Park, Illinois.