An advocate of this system.

in the same sense (also attributive or as adj.).

a person who advocates a form of socialism based on Christian principles; spec. a member or supporter of any of various political parties advocating…

A person who believes in or advocates societarianism; (also) a socialist. Now rare.

An advocate of democratic socialism; a member of a political party whose aims are those of democratic socialism. Cf. social democrat, n.

An advocate or supporter of social democracy; spec. a member of a political party that advocates social democracy.

An advocate of utopian socialism (utopian socialism, n.). Opposed to scientific socialist, n.

Originally: a socialist whose theories are systematic. Later: an advocate of scientific socialism; esp. a Marxist. Opposed to utopian socialist.

An advocate or supporter of state socialism.

A person who espouses socialist ideals but enjoys a wealthy lifestyle. Cf. limousine liberal n. at limousine, n. b, champagne socialism, n.

An advocate or supporter of state capitalism.

Politics. A member of a similar group outside the Soviet Union, or of any extremist political group.