While serving as a senator from Missouri, Truman rose to national prominence as the leader of the Truman Committee, which investigated wasteful and inefficient practices in wartime production during World War II. As the war continued, President Franklin D. Roosevelt sought re-election in the 1944 presidential election. Roosevelt personally favored either incumbent Vice President Henry A. Wallace or James F. Byrnes as his running mate in 1944. However, Wallace was unpopular among conservatives in the Democratic Party, while Byrnes was opposed by liberals and many Catholics. At the behest of party leaders, Roosevelt agreed to run with Truman, who was acceptable to all factions of the party, and Truman was nominated for vice president at the 1944 Democratic National Convention.