The Progressive Party has existed in several forms.
Theodore Roosevelt ran as a Progressive in 1912, finishing second ahead of President William Howard Taft. This granted the Progressive Party ballot access in a lot of states, but the Progressive Party withered as a separate entity by 1916 when they fielded no Presidential nominee.
Robert LaFollette was considered a Progressive party candidate in 1924 (although he ran under other labels in some states)
Robert LaFollette, Jr. helped form the Progressive Party of Wisconsin which existed from 1934 to 1946 and won numerous offices.
Henry Wallace also ran as a Progressive in 1948. Although not directly connected or supported by most of the previous Progressive Party members (and unable to use the Progressive label in Wisconsin). Wallace finished 4th with a disappointing percentage.
Currently the Progressive Party has elected officials in Vermont. Where most of the current Progressive Party activity is conducted these days.