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Radio (1944–1945)

The idea of doing a radio variety show occurred to Welles after his success as substitute host of four consecutive episodes (March 14 – April 4, 1943) of The Jack Benny Program, radio's most popular show, when Benny contracted pneumonia on a performance tour of military bases. A half-hour variety show broadcast January 26 – July 19, 1944, on the Columbia Pacific Network, The Orson Welles Almanac presented sketch comedy, magic, mindreading, music and readings from classic works. Many of the shows originated on U.S. military camps, where Welles and his repertory company and guests entertained the troops with a reduced version of The Mercury Wonder Show. The performances of the all-star jazz group Welles brought together for the show were so popular that the band became a regular feature and was an important force in reviving interest in traditional New Orleans jazz.

Welles was placed on the U.S. Treasury payroll on May 15, 1944, as an expert consultant for the duration of the war, with a retainer of $1 a year. On the recommendation of President Franklin D. Roosevelt, Secretary of the Treasury Henry Morgenthau asked Welles to lead the Fifth War Loan Drive, which opened June 12 with a one-hour radio show on all four networks, broadcast from Texarkana, Texas. Including a statement by the President, the program defined the causes of the war and encouraged Americans to buy $16 billion in bonds to finance the Normandy landings and the most violent phase of World War II. Welles produced additional war loan drive broadcasts on June 14 from the Hollywood Bowl, and June 16 from Soldier Field, Chicago. Americans purchased $20.6 billion in War Bonds during the Fifth War Loan Drive, which ended on July 8, 1944.

Welles campaigned ardently for Roosevelt in 1944. A longtime supporter and campaign speaker for FDR, he occasionally sent the president ideas and phrases that were sometimes incorporated into what Welles characterized as "less important speeches". One of these ideas was the joke in what came to be called the Fala speech, Roosevelt's nationally broadcast September 23 address to the International Teamsters Union which opened the 1944 presidential campaign.

Welles campaigned for the Roosevelt–Truman ticket almost full-time in the fall of 1944, traveling to nearly every state to the detriment of his own health and at his own expense. In addition to his radio addresses he filled in for Roosevelt, opposite Republican presidential nominee Thomas E. Dewey, at The New York Herald Tribune Forum broadcast October 18 on the Blue Network. Welles accompanied FDR to his last campaign rally, speaking at an event November 4 at Boston's Fenway Park before 40,000 people, and took part in a historic election-eve campaign broadcast November 6 on all four radio networks.

On November 21, 1944, Welles began his association with This Is My Best, a CBS radio series he would briefly produce, direct, write and host (March 13 – April 24, 1945). He wrote a political column called Orson Welles' Almanac (later titled Orson Welles Today) for The New York Post January–November 1945, and advocated the continuation of FDR's New Deal policies and his international vision, particularly the establishment of the United Nations and the cause of world peace.

On April 12, 1945, the day Franklin D. Roosevelt died, the Blue-ABC network marshalled its entire executive staff and national leaders to pay homage to the late president. "Among the outstanding programs which attracted wide attention was a special tribute delivered by Orson Welles", reported Broadcasting magazine. Welles spoke at 10:10 p.m Eastern War Time, from Hollywood, and stressed the importance of continuing FDR's work: "He has no need for homage and we who loved him have no time for tears... Our fighting sons and brothers cannot pause tonight to mark the death of him whose name will be given to the age we live in."

Welles presented another special broadcast on the death of Roosevelt the following evening: "We must move on beyond mere death to that free world which was the hope and labor of his life."

He dedicated the April 17 episode of This Is My Best to Roosevelt and the future of America on the eve of the United Nations Conference on International Organization. Welles was an advisor and correspondent for the Blue-ABC radio network's coverage of the San Francisco conference that formed the UN, taking place April 24 – June 23, 1945. He presented a half-hour dramatic program written by Ben Hecht on the opening day of the conference, and on Sunday afternoons (April 29 – June 10) he led a weekly discussion from the San Francisco Civic Auditorium.