J(ohn) Henry Stump (June 4, 1880 – May 15, 1949) was an American Socialist politician and mayor of Reading, Pennsylvania 1927–1931, 1935–1939 and 1943–1947.
Stump left the Socialist Party of America following the Old Guard faction's split and helped form the Social Democratic Federation. He served as vice-chair of the SDF along with John Shenton of Connecticut.
At the SDF's founding convention in 1937, Stump spoke critically of his former party, stating:
“We came here because we could no longer square our Socialist conscience with remaining in the party which has fallen into the hands of disruptors, of people who do not believe in the idea and ideals of democratic Socialism. I am confident that at this convention we will build an organization that will truly represent these ideas.”