Johnson steered the projects towards contractors he knew, such as Herman and George Brown, who would finance much of Johnson's future career.[26] In 1941, he ran for the Democratic U.S. Senate nomination in a special election, losing narrowly to the sitting Governor of Texas, businessman and radio personality W. Lee O'Daniel. O'Daniel received 175,590 votes (30.49 percent) to Johnson's 174,279 (30.26 percent).

Active military duty (1941–1942)
LCDR Johnson, March 1942
Johnson was appointed a Lieutenant Commander in the U.S. Naval Reserve on June 21, 1940. While serving as a U.S. representative, he was called to active duty three days after the Japanese attack on Pearl Harbor in December 1941. His orders were to report to the Office of the Chief of Naval Operations in Washington, D.C., for instruction and training.[46] Following his training, he asked Undersecretary of the Navy James Forrestal for a job in Washington. He was sent instead to inspect shipyard facilities in Texas and on the West Coast. In the spring of 1942, President Roosevelt decided he needed better information on conditions in the Southwest Pacific, and to send a highly trusted political ally to get it. 