In 1906, Rosewater helped his father run for the U.S. Senate as a Republican, yet unsuccessful against Norris Brown, who was also a Republican. His father died on August 31, 1906 and he took over as managing editor of the "Omaha Bee", becoming editor the following year. At the time of his death, Rosewater senior had been involved in plans for launching the American Jewish Committee, and Victor assumed his father's role, becoming a founder of the AJC. He was a Nebraska delegate to the 1908 Republican National Convention and a member of Republican National Committee, 1908–12, serving as its chairman in 1912 and planning its convention that year.