Randall was a member of the California State Assembly from 1911 to 1912.
In 1914, Randall was elected to the United States Congress as a member of the Prohibition Party. Randall won 28,097 votes (30.9%), Congressman Charles W. Bell won 27,560 votes (30.3%), Republican Frank C. Roberts won 25,176 (27.7%), and Socialist Henry Hart won 10,084 votes (11.09%). Taking advantage of California election laws at the time, Randall was re-elected in 1916 as the nominee of the Prohibition, Democratic, Republican, and Progressive parties defeating Charles W. Bell (running as an independent candidate) by the margin of 58,826 to 33,270 (57.8% to 32.7%) with 9,661 votes for the Socialist Party candidate. Randall was re-elected by a 38,782 to 31,689 (55% to 45%) margin over a Republican in 1918. He is the only person designated as a member of the Prohibition Party to ever serve in the United States Congress. Randall was defeated for re-election in 1920 by a Republican, by margin of 62,952 votes (60%) to 36,675 votes.
Randall ran in 1922 (45,794 votes and 41%), 1924 (67,735 votes and 36% as a candidate of the Prohibition, Socialist, and Democratic parties), 1926 (61,719 votes and 38%), 1934 (18760 votes and 14% as a Progressive), and 1940 (36406 votes and 22% as a candidate of the Prohibition and Progressive parties).
Randall was the Vice Presidential candidate for the American Party in 1924, winning 23,867 votes (0.08%).
Randall was also the first person to represent the first district of the Los Angeles City Council under the new charter in 1925. He served until 1931.