In 1949, Cannon returned to politics, winning election as city attorney for Las Vegas, Nevada.

After leaving the Senate, Cannon remained in Washington as an aviation and defense consultant for nearly a decade before retiring to Las Vegas in the mid-1990s.

During summers, he worked as a bell hop at the North Rim Lodge along the Grand Canyon.

In the summer of 1936 after his graduation he directed an orchestra of four, performing on the SS Jefferson on a cruise from Seattle, Washington, to Yokohama, Japan.

Assigned to the European theater, he dropped paratroopers at Saint-Come-du-Mont, Normandy and during the following combat mission in September 1944 was shot down over the Netherlands.

[8] His military decorations included the Silver Star, Legion of Merit, Distinguished Flying Cross, the Purple Heart and the Air Medal (three awards).

Cannon was nearly defeated in his first re-election bid in 1964, holding off Republican Lieutenant Governor Paul Laxalt in one of the closest Senate elections ever.

Cannon was re-elected with far less difficulty in 1970 by defeating Washoe County District Attorney William Raggio.

In the early 1980s, Cannon was ensnared in a scandal when Teamsters President Roy Lee Williams was indicted by federal prosecutors for attempting to bribe Cannon in exchange for using his influence to block the Motor Carrier Act of 1980, a bill deregulating the trucking industry.

Cannon was challenged in the 1982 Democratic primary by U.S. Representative Jim Santini and won winning by about 4,500 votes but lost the general election to Republican nominee Chic Hecht, a former state senator and businessman.

[13] Deregulation led to lower air fares and contributed to the growth of Las Vegas as a tourist destination.

[14] Americans for Democratic Action, an organization that has long issued 100-point "Liberal Quotient" scores to members of Congress, rated Cannon a 69 in 1965,[15] 41 in 1971,[16] 30 in 1977,[17] and 50 in 1982.

[25] After leaving Congress in 1983, Cannon remained in Washington as a defense and aviation consultant for 11 years.

[12] On February 2, 1988, President Ronald Reagan nominated Cannon to the inaugural Board of Trustees of the Goldwater Scholarship program.

[27] On March 5, 2002, Cannon died at age 90 in a Las Vegas hospice due to congestive heart failure; he was previously diagnosed with Alzheimer's disease.